Momo is best girl for having best character development, edgy sensei has good point, the true culprit is not the one you think and the enemy of your enemy is your friend.

I really regret reading this garbage of a story. If you value your time, don't read this. It has shitty story and characters with no souls. Idiot students keep doing fucked up shit for no reason. It's as if they are not at school but in an asylum. Every fucking student is mental, all of them have mental issues and as a wonderful coincidence they are all in the same class. On top of all this bullshit as you guessed there is sexual violance. That's right these idiots keep thinking if they use some rape scenes they are some literary genuis. Don't get me wrong you can use that kind of a concept in your story if it's necessary. But what happens is some girl abduckts her classmate ( it doesn't show how she does it) all of o sudden she is tied up in a room and bunch of rapists are with her ( i don't know how a highchool girl can find rapists and convince all of them to come to closed room with cameras).
Just read some better manga don't waste your time on this crap.