
I was trying to come up with a cool introduction to this review, but I kinda forgot after thinking about the series and started laughing at some of the relatable moments depicted in this incredibly heartwarming anime.

If you're reading this and you want the TL;DR, here it is: Four (and then Five) Cool looking guys go through life being very clumsy. Now, let me explain why that is such a good thing for you, no matter who you are.
The most accurate description I can give Cool Douji Danshi is "A palate cleanser for your soul", why you may ask? It's because this anime will make you feel a warmth in your chest no matter when or where you watch it.
A 24 half-lenght chapter series that leaves you with a feeling of wanting more but satisfied enough to not feel boring will capture your heart and your smile in the most wholesome way.
NOTE: This is a review free of spoilers for 90% of it length, there are minor spoilers ahead.
Now for the "review" aspect. Cool Douji Danshi is a really good series, doesn't feel stiff with both story and animation, which is an aspect you will find in most slice-of-life stories where either of those things lacks some sort of polish.
This particular story is about four very good looking guys just doing their best while they have to live with a very peculiar situation, they all are very clumsy, and in their own way, they try to not be bother by those awkward situations.
We have an adult office worker (Mima Takayuki), that doesn't care about situations that are weird for him and is kind of a workaholic. A somehow nerdy university student (Ichikura Hayate), who is the personification of "I'm going to use my phone's light to look for my phone". The energetic yet serious high school student (Futami Shum), who's very good at sports but blunders basically everything else. And a vocational school student (Shiki Souma), the stylish type that's all smiles no frown.
Towards the end of the series we're introduce to a fifth main character (Igarashi Motoharu), an acclaimed writer who is actually a childhood friend of the office worker, and is with his introduction that this series changes in a non-dramatic yet very impactful way.
When the character of the writer (Motoharu) appears, the series starts to get a bit more into the "let's try to help these characters with some anxiety problems" by giving most of them a support character that basically fills the role that the cool guys need. A reminder of what's important for Mima, a friend and some sort of beacon for Hayate, and a push into action for Souma. For Shun is a little complicated, given that Shun is mostly already done with his development at this point, but still, Motoharu comes in the form of motivation for Shun to keep improving in the areas he's not particularly strong.

Giving that there's no real plot to the whole series, you could make the duration of each "arc" as long or as short as you want. Now, to answer the question that you probably are asking to your screen right now, why do you put quotes to the word Arc?
Easy, because there aren't any arcs as we know them. That's because almost every single episode has its unique story, yes, I said almost every episode. There are a couple of episodes that continue the storyline from the previous one directly, more specifically, the last two episodes are basically one long chapter.
This idea of having a series chapter based definitely sets a pace that, as previously mentioned, leaves a feeling of wanting more and yet is enough. Combined with how every episode is almost 12 minutes long (with both OP and ED) it just feels right. Making it longer or having more chapters could affect the perception of the viewer, making it feel slower or even sludgy at times.
The last strong point I would like to make in this review is that one of the main points of the series is presented and not touched that much, and that's the "Cool" part.
Yes, the guys are very handsome, yes, they are very cool and at first glance you could think "This is definitely a BL story". But this is what I like to call "An implied topic", and that's thanks to the series not shoving that fact in the viewers face every two or three seconds. Sure, there are moments when this happens, but is almost imperceptible, to the point where you'll be thinking "Oh yeah, they are supposed to be hot".
In conclusion, Cool Douji Danshi is the whole package, good-loking both inside and outside. You will say yes in a split second if this anime asked you to have dinner tomorrow night.