Mild spoilers in
Cavalry arc was really stretched out tbh, and the chairmans subplot was so weird but then again what isn't weird in this manga.
There are many questions left to be answered, like why chairman was imprisoned, why was that prison built in middle of the school, why is Mari suddenly going abroad etc.
And the ending feels right but off at the same time, I feel like there should be a sequel where Kiyoshi tries to win the forgiveness of Chiyo and so on.
I also felt really bad for Kiyoshi throughout the manga, feels like he is the MAIN character but we see him less and less as the manga goes on, and he has to take the huge hits for everything that it's actually a miracle that the guy still has a sane mind, then again he actually doesn't and almost committed suicide once.
Also our boys grew more distant by every chapter, Andre found a girlfriend, Anzu and Shingo's relation is questionable, Gakuto went full retard mode and lost his chances, Joe I don't even know anymore, when was the last time we saw him tending to his ant farm?
This manga definitely couldn't follow the pace of it's first arcs, as for why I can't get my finger on it.
I'd gives this a 7/10, if it wasn't for the stretching in cavalry arc it would be a 8/10.