Setting
In a world with no sun only a limited man-made sun shines, there are giant insects seeking the "heart" of people and letters, so "letter bees" are tasked with the dangerous task of delivering the letters.

Story
It starts being Lag Seeing, who had his mother taken from him, being delivered as a "letter" to be taken care of, from that point onwards he decides he wants to be a letter bee too, and wants to deliver letters as well as find his mother.

Art
The line art is generally good, I'm not a big fan of high-contrast shading, but it doesn't bother me much here. Though generally, the author will bring some weird looking asses and disrupt the tone of the manga (as well as my appreciation for the manga in general).

Spoilerless review
While I didn't like it at all, I can see others enjoying it, and the best way to judge it is probably to read 2-3 volumes, if you don't like them, I doubt you'll like the rest, but if you like them, you'll probably like the majority of it.

Personally, I wasn't really invested in the main cast of characters nor the bigger plot, and the bad people from the short stories lacked any nuance whatsoever, mostly there for some cheap tragedy or revenge porn - which might appeal to some, but I found underwhelming.

The fights, while competently drawn, lacked any tension to me, and I was just watching the clock for them to finally end, and the jokes I found to be a mixed bag. In general, I enjoyed the gags involving animals, special mention to Steak, but the ones involving humans were more hit-and-miss for me, specially those related to Niche as they had a high chance of being ass jokes.

From this point onwards, expect SPOILERS.

Characters
I had a hard time sympathizing with the characters, a lot of them seemed to exist to fulfill some sort of role: Zazie was the lone wolf that learns to trust his friends, Jiggy the ultimate "cool" guy, LLoyd the "mysterious" guy, and so on…

Then you have characters like Thunderland who is introduced as some sort of monster that will stop a nothing to dissect animals just to then show he's a good guy, all in a way that felt like it was there to be just padding... him running with Steak made sense when he was what he was originally implied to be, not after the reveal he had been taking care of the cats rather than dissecting them and what not.

From the main cast, I'd say that my favorite is Connor, unpretentious and easy going, he just loves to eat.

For the letter bees in general, I'd say that Lily Confort. And I think the author did her dirty by snatching her heart instantly when you had pages upon pages to recover a heart when the plot called for it.

Setting
You'd think that something like having no actual sun would have a huge impact in the world, but what we know is that there are essentially 3 areas of different levels of riches based on how far they are from the sun, but it's not like any reason is giving for this. It's only like 15 volumes when we see many plants in the capital... but then we also see a giant forest outside the capital, so what gives?.

We also don't see goods being sent around, other than letters, it really doesn't seem like the capital sends food outside, yet, even though we see a few plants around plants, we don't really see crops around, it's a wonder how towns sustain themselves when even outside far off towns there's only fucking rocky terrains, rocky terrains everywhere.

I thought it would have other effects as well, with some places living in constant darkness, and others living in constant light, but I saw nothing of the sorts being seriously touched upon.

Story
As I mentioned, I wasn't really invested, and the fights just dragged the pacing down, specially when Reverse called the gaichuu, and it took multiple volumes to resolve, and even then, it's unclear what the fuck they were planning to do with that. So it eats the "man-made" sun which is actually a gaichuu... now you have another giant gaichuu and no sun, so what the fuck have you achieved?

And the closer it gets to the end, the more the manga drones and drones about information I couldn't care about, bogging down the pacing more and more.

The story was supposed to be about Lag searching his mom (which is eventually replaced with finding Gauche instead, and then the mother topic is dropped for most of the manga) and delivering letters, so I thought we would have more individual stories about the letters. But there are surprisingly few considering that this is 20 volumes long.

While I can't say I loved them, I still liked them more than the main plot in general. Something that got in the way was how people were often sinless victims or absolutely garbage with no redeeming qualities, with not much in between. And in the off-chance we got an ok story - like the working mother whose daughter died while she was out - there's a big chance there'll be obtrusive asses drawn and kind of focused by the shading and affecting the tone of the scene.

My favorite story was the one about the lighthouse

Nitpicks
Back when Reverse was leading the Gaichuu, Lag goes to help the human sacrifices but encounters Gauche and a verbal battle ensues before the actual fight, which ends with Lag getting really mad at him when he hears people got their heart taken. But while Gauche was placed there to hinder letter bees... at no point does Lag try to avoid him to go save the people, not only that, the one managing logistics and leading the people there was Roda, who was right there, but Lag is mad at Gauche specifically enough to say he'd kill him, while he grabs Roda who was falling to her death (which wasn't her death of course).

While Gauche is the one to take the Gaichuu of the ice, it's not clear how he achieved it when it's supposed that Maka doe shit that prevents people from entering, a thing that wasn't done when Lag came because he was with Niche.

There are several kinds of Gaichuu, and there are several of said kinds, yet somehow Zazie knew that X Gaichuu was the one who killed his parents? While a lot of Gaichuu live in specific areas, this one moved around which is why it took him years to find it, but that's even more of a reason to not know if it is the same one...

It's never explained why the majority of bees are teens or even early teens, you'd think adults would be better suited in general for this dangerous task, but there are very few of them that we actually saw.

While Lag got Sylvette's heart back, I don't think it was explained what happened to everyone else who had lost heart, because - if he could return hers - he should be able to return Gauche's, Lily's, Sunny's and more...right?

And in general, whether someone survived or died after losing heart seemed to be mostly on the whim of the mangaka.

You might also think you'd get fake mailmen too, or at least a cheaper, less curated, unofficial alternative considering it was said they were very expensive... but nope.

Conclusion
I wanted to be kinder to this manga - the premise is interesting and has a lot of potential, the art is good, and there's a big focus in a large cast of characters - but the execution doesn't work for me at all.

I didn't connect with most characters, making the individual stories underwhelming for the most part, and making the overarching story a chore to read rather than interesting. Sealed with the fact that I couldn't find anything to be excited about in the battles.

I also think that the way the author drew asses, crotches, and (sometimes) crotches, went against the kind of tone he probably wanted to set. Or at least it's my impression that it was supposed to be a sometimes heartwarming, sometimes bittersweet, story of putting your all to win against impossible odds and help your friends and all that jazz.

Looking back, the only thing I remember fondly is some gags, and that just isn't enough.

No Spoilers

This "review" was originally intended to exist as a note in my list, but having gone over the character limit, I had to turn it into a review. First I'll talk about the setting, initial story and characters in a way that hopefully doesn't spoil those who haven't read it, but after a marked cut off point there will be spoilers.

Setting

The setting feels lazy, you have dungeon portals that appear at random and can only be entered by "awakened" people, they enter to get objects from the enemies and the dungeon itself and because if the dungeon isn't taken care of in 7 days (oddly there seems to be no variance in time) the monsters can go through the portal into their worldand wreak havoc. Awakened people have different rankings based in some sort of magic power that doesn't change[0], while you can get equipment to do better your actual magic power doesn't change.

Despite the existence of dungeons the rest of earth is pretty much parallel to real life, the economy is fine, there doesn't seem to be much of an impact in the world[1] (ignoring areas that were destroyed). Despite the dungeon containing materials not found on earth it doesn't appear it's being used to develop any sort of technologies besides medieval looking equipment that's only going to be used in the dungeons, so basically what happens in a dungeon is isolated from the world, I'd have expected these drastic changes in human activities would have meant changes in how our civilization develops, but nothing of note.

Story

The protagonist is the weakest of the hunters and makes very little money off it, barely enough to pay the hospital bills for mom, and getting behind on rent. He doesn't make enough to buy equipment to slowly get more money out of dungeons, he barely makes enough to scrap by, and he's normally the only one getting wounded in low level dungeons. Even though he could die, even though he's barely making any money, even though he isn't slowly improving or anything, and that the economy is working normally, he still works as a hunter. It's not explained why he doesn't take a normal job when he makes so little and if he died his sister would have to stop studying to begin working, it was never established why he had to do this job of all things.

If the economy was fucked, and he had nothing else to scrape enough? Fine. If hunters automatically got health insurance that affect direct families? Fine. But none of these things are in the setting.[2]

Then there's all the gaming stuff I just didn't care about. It's not just the "system" (which gets sort of explained later), it's the icons over people (which strangely only seems to appear in season 1), the medieval fantasy equipments, all that stuff, just makes it harder tot ake it seriously.

Characters

We have an S ranker looking for revenge, a serious A ranker that works for the government keeping things under control, a B ranker that's too afraid to go to high ranking dungeons[3], a C ranker that's getting old and after a lapse in judgment still decides to move forward, a sister that's willing to stop studying to prevent her brother from being hurt, and the protagonist who risks his life in order to pay for his mom's bill and his sister's school. You'd think this would be enough you get the ball rolling, but I was disappointed by how little these are explored, making them feel shallow, but it's to be expected that something called solo leveling would mainly focus on the protagonist...

The problem is that the protagonist isn't appealing to me, what we see is someone seeking to get strong, which makes sense given how weak he is, but not much else. There's just enough character for a power fantasy, which might be enough for some people, but not me.

Fights

[4]

Normally one expects protagonists to survive thank to plot armor, as an author you have to make him or at least the people around him feel vulnerable, but when the protagonist can get a power up from thin air, it's basically impossible for me to feel any tension.

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Minor detail but the author likes to hide the faces of new strong characters... even if their face is going to be revealed in the next chapter, why even bother with hiding them at all?

Spoilers

[0]Except people can be re-awakened in a very unlikely event that isn't really explored, we just know that it happens but that's it. And we letter learn that there are a handful people that actually help people increase their magic power.

[1]The only exception seemingly being the machines made to keep alive those suffering from eternal slumber, but functionally they're the same as machines keeping comatose people alive. You could switch them around and nothing would change.

[2]About 1/3 through, it's revealed that MC's dad was the big cheese, and even he got sent to the shadow realm. Even LESS for the weakest of the weak to go be a hunter.

[3]She then gets PTSD after barely surviving a possible rank S encounter but keeps on chugging, but again, this isn't properly explored either, missed opportunity.

[4]I can't find any tension here when the main character can do whatever, when he fought the blue snake I expected him to bail out due to the difference of strength and experience, but after being hit around he won in one shot. Granted, he hit a weak spot, and the fight alone might be justifiable but...

Then he fights Cerberus, which was a lot stronger than him, a monster he couldn't put a scratch on, and then it used a skill to get even stronger, and what does he do? Just restore his status back to square one to recover his life and fatigue, yet he basically insta-kills Cerberus after that.

Overall

I found the story forgettable, the setting lazy, and the plot just unengaging because there's generally very little reason to feel any tension when MC is present, and when he isn't the characters are generally not something I care about - the only time I considered there was a proper urgency, stakes, and goal, is when sister was in the school with the orcs.

The characters themselves are mediocre, not great, not terrible, but not much exploration of what they think and why, there was an attempt with sister and Myung around 3/4 into the manhwa, but it was too little too late.

There's just the bare minimum for the power fantasy to be viable, introduce some asshole character that scoffs at MC so they can get wrecked, or have people witness how strong he is and be amazed by his feats. Feeling smug as MC plows into his enemies is the main dish served by this manhwa.

The art is great, there are a few derpy eyes here and there, but there are good colors, composition, perspective, sense of speed, strength and scale. I'm amazed the artists managed to put these out weekly...

...but when I'm not engaged in the battle due to there being no danger and tension, I can't get excited by the battles, and, at that point, the art is just being wasted. Had this been shorter, I probably wouldn't be so tired of its formula, but for a 180 chapters work, it feels pretty barren in most regards.

The issue becomes more apparent the longer the manga runs, the power level just goes crazy, and the last stretch of the manga becomes so weightless that it's just a slog to read through, finishing with an end that left me feeling nothing - I was neither happy that those who died were brought back, nor saddened by the sacrifice MC had to do in order to achieve it, I just didn't really care because no character had an impact on me, MC included.

I can understand why people like it, if you can get into the battles, the art does the rest, unfortunately, I just couldn't get into the battles. And I tried to get in the mood, songs from metal gear rising, two steps from hell, ace attorney all failed me.

Significant plot points

MC tries to convince sister's friend to quit being a hunter, he learns about it when visiting school and gets asked by a teacher as she doesn't want to come to class to become a hunter despite being rank E. He decides to discourage her by bringing her to a high level dungeon, and they end up in a red gate. Despite the fact that an A rank and a bunch of B ranks he fails at convincing her to quit, she disappears from the manhwa shortly after, and reappears during the goblin school arc, even though she was going to quit school to become a hunter and MC failed at convincing her otherwise?

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Dong Su gets called to America because they find a powerful South Korean that might be a monster, though strangely Dong Su says his business in SK was over, even though he might think that MC is dead or stuck in a red gate... he had 2 targets, the other one he never touched at all so that's just a lie. Also, after he gets defeated, he loses all relevancy without actually having accomplishing anything.

Dad suddenly appears 1/3 into the manhwa, he hadn't been mentioned up until that point, he comes out of a gate as he had been lost in a closed gate for 10 years. And he appears by taking care of a party setup for an A rank dungeon, and then an S ranker (Dong Su), not before saying that there was a big crisis that had to be adverted, but of course, not giving any details about what the crisis is, just to try and create some cheap suspension.

He then proceeds to disappear for over 100 chapters.

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The mom appears for the first time about 1/3 through the manga and gets healed midway through. She appears so late, so little, and we're given so little backstory that when she was finally healed I couldn't have cared less about it.

I'm willing to admit I might be a jaded asshole, but I don't think we were given any reason to actually care about her.

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The start of jeju island arc didn't sit well with me for 2 reasons:

a) Every victim we see from the Japanese side is killed in one shot by super ant, normally aiming at their head, but when it comes to the Korean tea... they get non-fatal wounds, why? The ant then leaves, killing only the healer so that they can be left wounded and then be "rescued".

b) How long MC takes to teleport, it was already shown that he was aware of an attempted murder by a normal person, than to his shadows. So how come he didn't teleport before they got wounded? Just so they can be wounded and rescued by him, the author is so transparent that it just doesn't feel right to me, it's a transparent attempt at raising the stakes. But you know, MC has to LOOK cool.

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When MC finds the chained monarch, just before he frees him he says that the magic crystal in his neck means that he can hear the voice of the rulers............ when the fuck was this established? We do know that the rulers issue the command to kill humans to the monsters, but when was that connected to magic crystal walkie-talkies? Did I just miss this somewhere? Was it the translation I was reading? Where? When? How?

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Mom decides to stay on the apartment (which I called to be due to dad and I ended up being right), saying that MC will protect them just like dad did, never mind he had been gone for 10 years at that point. She desists on the idea the moment he dies, despite that she should have no reason to know other than some nebulous intuition (and not like being there changed anything about his death).

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Towards the end the power scale becomes completely ridiculous, even between monarchs the power difference is huge just to justify MC moping the floor with a few but then having trouble with the ones to come.

He gets a limitless regeneration (that isn't limitless) out of his ass, dies and gets fucking stronger, and then even stronger by connecting to his pokebank and retrieving his old army. Then we learn that monarch of the shadows has the power to rickroll people for some people, what does showing memories to people have to do with controlling the dead - no idea.

And for some reason, even though the whole premise of the series is to come into a dungeon portal to defeat what lies inside before they break free and fuck up people, towards the end they wait for the monster to pour out instead. Why? Why? You even have the advantage coming in because you can retreat after doing some damage and coming back. The only exceptions to that being red gates, and MC has only found 2 despite the many ones he's cleared, and one that had a spell put on it to prevent them from escaping, which MC being MC should be able to break, and yet again we saw a single time, even the one that had the chained monarch had no spell to prevent exitting it, and even then MC's been shown to be able to leave dungeons by exchanging himself with a shadow, so event hen it wouldn't have been an issue now that at this point he knows he can leave with people

Also love that he has more than enough shadows to place a few at every gate and use his shared senses to know what's happening everywhere as well as be able to teleport elsewhere if need be, but doesn't really, he manages to have one in canada just because Adam happened to be there, but it certainly was a great oversight.

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When the deus ex machina time travel device was mentioned, it was said that the rulers hadn't managed to gain the upper hand because the monarchs' memories weren't affected so each time they were more effective, and they had always failed to get rid of them as a result. Despite the act that the last rewind is done after all of them are killed, they seem to still be disorganized and the strongest one, the dragon monarch still decides to properly engage only after everyone else is already dead, very intelligent strategy and a good use of being aware of your loses.

Setting nitpicks

Something I wondered for a while, is why you didn't see anyone using weapons like guns, at least the healer should have one in the low-ish rank dungeons, if the healer is toast the party is likely toast as well. But you know, we need to have almost every character looking straight out of a medieval fantasy setting. It's not until chapter 131 - about 3/4 into the manhwa - that new technologies don't much affect the creatures, no explanation given, and this coming after Jeju island where they used battleships and no mention of this whatsoever.

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There's also the monster language, so hunters can't understand what they say, but somehow at the start we see the C ranker reading runes, how? We don't really see any efforts at understanding and integrating knowledge from the other worlds, the only instance we see anyone other than MC getting information from them is the C ranker at the very start of the manhwa, never explained how he could read it, nothing done with that skill other than that specific part.

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The existence of red gates isn't really explained, if the idea is to strengthen humans and earth in order to survive the clash, why would you place death traps that hide their actual ranking and prevent people fro coming out? It's just going to kill most of the same people you're supposedly trying to give strength to.

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A mystery throughout most of the manhwa is how the system works, which is what sets MC apart from everyone else, as it continuously allows him to grow. It is eventually revealed that it exists in order to allow for MC to slowly gain control of the monarch's power, as it'd be too much to take from the start...

But where does that leave stuff like the crafting system, and the shop (which was even locked at low levels)? What could those possibly have to do with controlling the undead. I guess shadow monarch just has ebay powers.

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So as I understood, the gate portal backfired on MC's dad, causing him to be trapped, it's just weird is that - as far as I can remember - is the only case mentioned in the manhwa, so the reason wasn't all that satisfactory to me. He also mentions how the "great disaster" awakened soon before disappearing, and we never get to learn what he meant. The monarchs as a whole? Just the dragon monarch? But were they even sleeping? I don't recall that being mentioned, at least.

I wasn't planning to make a review, but I ended up surpassing the character limit of the notes system, and while I went through it to fix it up a little, there might be some jank within.

What I can say before running into spoiler territory is that we have a setup in which the protagonist, as the next successor of his family known for spiritual powers, handles paranormal cases. While the cases are not brought up again after they end, there's a story that develops between them and sometimes while in the cases.

After this point there are spoilers.

The manga is about Subaru, the 13th successor to his clan who work to settle paranormal cases, he has a twin sister called Hokuto who has little spiritual powers, so she wasn't chosen. They are often together, the protagonist is a goodie and kinda bland protagonist, while Hokuto is outspoken, and always telling her brother to go out with Seishirou (who is 9 years older than him, and apparently Subaru is 15 when they meet, and maybe 16 when it ends, pretty creepy), a veterinarian who's always professing his love for Subaru.

Often, when they meet, we have Seishirou pushing himself onto Subaru (not physically, usually), Subaru blushing and his sister teasing him. There's quite a bit of that in this manga for some reason, specially at the start. In between these antics there are paranormal cases, sometimes spirits clinging to a place, and sometimes the living meddling in some way with spirits, not all of these cases have a happy ending.

The problem is how they try to build suspense for stuff that will appear much later, they mention the glove Subaru wears, that he must not take off for any reason, the thing is even he doesn't know why, he's just listening to his grandmother, the previous head of the family. The gloves are brought up a few times through the manga maybe in case we don't forget, but it's still a bit annoying to keep bringing them up without actually provide information on why they are important, and this happens with something else as well.

Now the thing is that the Sumeragi clan isn't the only clan known for its spiritual powers, the Sakurazuka clan is known to use spiritual powers for murder But while Sei has the Sakurazuka surname, it's common so it doesn't mean he's part of the clan. However, it's revealed early on that Sei possesses some powers, and while we see some otherwise normal people using incantations, the fact that he can and with his surname, it should make some alarms ring on Subaru's head, and while he thinks about it a little at some points there's no real effort put towards finding out if it's the case.

Now back to the sister, as her brother is often doing spiritual works, she often cooks for her, apparently she's good at cooking and baking, and while she isn't good with the spiritual she's adept at fighting (we never see her actually training, and it's never important to the story, she only beat some policemen in a side story where none of the other main characters appeared). She also acts as moral support for Subaru in general, and loves to wear extravagant attires. While she's always pushing Sei and Subaru together, about midway through the manga she starts threatening Sei saying he better not hurt Subaru, despite this she keeps pushing them together.

A "bet" is often mentioned by Sei, generally muttered to himself, and a lot of those times he removes his glasses for dramatic effect, just like with the gloves the authors thought to "build suspense" by just mentioning something repeatedly in a dramatic fashion, heck, Sei even broke a mirror once when mentioning the bet so we don't forget. Eventually we see that Sei isn't afraid to hurt others and even murder, but these events are unknown to the protagonist.

At some point, a woman is going to slash at the protagonist and Sei gets in the middle and ends up losing his eye as a result, the problem is that there's no reason for this, he has shown how adept he is, even if you consider that he might not want to show his ugly side to the protagonist, he has already shown twice he can make people faint, once with Subaru and once with Hokuto, so he could have avoided being wounded altogether. From this, Subaru ends up realizing he truly loves Sei.

Eventually the lid over the secret is unveiled, the protagonist finds that he had met Sei 7 years prior. Sei had just killed a little girl, as he was the head of the assassin clan. While he'd normally kill any witnesses, he decides to make a bet, if they ever met again he'd try to love him for 1 year, if by the end he became a special person for him, he wouldn't kill him, and he marked his hands as he was now a target. Subaru's grandmother gave him special gloves to conceal the fact, not that it fooled him when he met Subaru in Tokyo 7 years after. Despite the year they spent together, and the affection he had shown, he never cared about Subaru, and was only saved because his grandmother managed to break his spell, but Subaru was left as if soulless due to the shock.

His sister feeling responsible ended up chasing Sei and being killed, which finally makes Subaru snap out of his trance like state, there's a time skip showing he began working again, is now smoking, and isn't cheerful like he used to be. He vowed to kill Sei and avenge his sister, but it ends without them meeting again as the last stretch was just so set up a sequel hook.

With all that said, the highlight for me were the cases, some more engaging than others, of course, but a lot of them contained criticism towards the Japanese society. Though some were just about the personal pain the people within the story suffered. Once the protagonist finds a woman trying to bury a dog's head to create an inugami to curse the killer of her little daughter, she was denied retribution by the justice system as he was declared insane, the protagonist channels her daughter's spirit in an attempt to stop her, and while the mother is able to see her spirit she can't hear what she says, but he can, and she's saying how much it hurt and that she wants the criminal punished, so the protagonist ends up lying to the mother to stop her (as cursing the man would end up getting her cursed as well). Though it's unclear if this case has a lasting impact on how he thinks, he's hurt and feels guilty about lying to her about what her daughter was saying.

The relationship of the protagonist with Sei, Sei's preventable wound, the protagonist putting 0 effort into finding more about Sei, the way it tried to build suspense with both the gloves and the bet and how it ended with a sequel hook are what ended up souring the experience to me. Although it was nice that just like some of the cases didn't get a good ending, there was no good ending for his love story. So in general in its exaggerations it ended up losing me, but others are likely to look past that or not care as much as I did.

Girl's last tour follows the protagonists Chito and Yuuri, while Chito tries to understand the world around her, and what happened in the past, Yuuri cares more about the now and rather than her brain, prefers to rely on gut feeling... as well as make sure her guts are filled.

The manga has beautiful, sketchy art that really showcases the desolate world the girls inhabit, shows dark nights - and sometimes days - cold climate, a gigantic, maze like, industrial complex that is falling apart in some places due to the lack of maintenance.

The manga has a strange pacing in which a lot of chapters seem to have considerable gaps in time between them as they find food in one chapter and in a few are already running low on it. Most of the time the girls will be using their vehicle to trek along to an uncertain destination.
While Chi takes care of the driving, repairs, cutting both of their hairs, manning the stove, reading signs, etc. Yuu just lazes on the back of the vehicle for the most part... when she isn't hurting Chi by touching a wound, cheating at games where food is at stake, (seemingly accidentally) throwing Chi's journal into a fire, outright stealing her food, etc. It makes you wonder if Chi is with her just because there isn't anyone else around.

During most of their trip they display an easygoing attitude, even when they are hurting for resources, this bundled with the fact that when they encounter some sentient being there's seemingly no interest in learning what's going on with the world, if there's a colony somewhere or anything else, makes it feel like they don't much care about what happens to them in the future. That way they meet Kanazawa - seemingly the first person they've met since they had to leave their town years ago - and soon after they're already saying goodbye.

But this happens with all of their encounters, when their vehicle breaks down, it does so near Ishii, a girl working on building an airplane to leave the city, who fixes their vehicle in exchange for the girls, or rather Chi, to help finish Ishii's airplane. Ishii soon leaves but the airplane breaks down, while Ishii is seen parachuting, she seemingly has no resources to survive, of course by this point she's already written out of the manga, so the girls simply go to their next destination after this.

This repeats with other encounters, although no more humans appear. At some point they encounter some weird life form with mushroom head that communicates through waves and tell them the end of earth is near... of course they don't ask for more information regarding this. Throughout the manga characters are introduced seemingly just to add some variety to it, and then get thrown out so we're back just to the protagonist pair.

This isn't everything that happens in the manga, it talks about humans' way of life, about how we view death, and how we find meaning in being remembered and passing down knowledge, but the way characters behave and interact seem ill-fitting for the most part.

Regarding the ending, my only problem with it is the build-up of expectation, for some reason both the mushroom heads and Chi's grandfather told them to go up... to find nothing. If they were going up just because they decided to go up, I'd have nothing to complain about, after all, there is no set path and you don't know where a road will take you, so might as well go wherever.