This episode is finally when things got really interesting for me. Kousetsu's sudden possession which led to the killing of Yumika is quite dumb imho though, like what?!
For me this anime is quite frustrating because I can see potential, but not people willed to extract it at all. The whole pacing is simply not acceptable and considering the promotion images it feels like they did not have a solid planning at all. Who the f introduces a school setting for being dropped 2 episodes after???
Kousetsu's possession was the most cheap thing I could imagine thrown, especially because the dude who is behind it doesn't feel like a serious villain at all. At least Koga were a bit interesting with their ideas.
So not only is this possession thing trying to go for an undeserved emotional event it goes and kills the mystery of what happened. Even if the thesis is incorrect, the introduction of this possession technique paints a pretty convincing picture that somebody used this technique to kill the previous Koga head and blame it on an Iga ninja. Considering the guy performing this technique also killed the inspector who realized what really happened in the video it only reinforces this theory.
This series is such a mess. I don't care about any of these characters, their villages, or what they stand for.
The way the villains manage to keep one-upping the protagonists from out of nowhere feels like that one kid on the playground who would keep inventing new rules to the game every time he started losing. I'm not saying the protagonists should have everything go smoothly by any means, but something contrived happening out of nowhere to immediately undo all the progress they've made is just frustrating by the fourth time it happens in a handful of episodes.