If Yumi ever develops an attachment to MC and finds out about Futaba, I would expect violence.
If/when Yumi becomes intimate with MC and Chika finds out, there will be violence (possibly against MC)
Self-harm is violence, and Rin is Rin.
Noriko is predictably violent. But fully half the girls could easily reach that point given the right set of variables, especially in the lead up to a reset when everyone's "settings" are wonky.
IF Yumi develops an attachment to MC ?
Ami might just kill if she catches sensei in the act with a girl, Makoto especially.
Maya would probably carry out a scientific experiement titles " In how many pieces can you chop up a Noriko ? "
Noriko will 100% kill Kirin is she figures out that she is crushing on sensei.
Drunken Sana might have a few things to say about her Sensei being stolen, especially after how much she opens up to him.
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The more I type, the more I feel like act 2 will be a battle rolaye.
Right, she's just being a tsundere at this point. As for Chika, she is one of the few that is fully expecting an exclusive relationship and is still unaware of his other relationships with the class and others outside it. However, she WILL find out, she's too smart not to figure it out eventually, and there WILL be something bad for player Sensei when she does. NEVER piss off Chika, that leads right into a bad time, though I don't think she'll ever get violent unless Chinami was involved and got hurt in the process, in which case he better run VERY far away, though she might chew him out for going behind her back and cheating. Ami WOULD kill if she caught another girl too close to him, she's far too unstable at this point and the same can be said of Noriko. I don't, however, see any significance to Makoto being the one he's caught with as opposed to a different girl. Maya I could see because then we're talking about Ami's best friend and Noriko's mortal enemy, both of which are much worse. As for Kirin, no, Noriko specifically states she's okay sharing with any girl who has no feelings for him and is just in a physical relationship with him. So far, the only girl that fits that description and is therefore safe is Kirin. Anyone else is as good as dead.
I don't think Yumi will actually care much about Futaba. The hate against her was never true hate, it was rather disappointment that she would not stand up for herself and fight (something Yumi has been doing her whole life, and that is the measures she is using here on Futaba as well). I don't even think she dislikes her at all, imo it is mostly projecting her own fears into Futaba and that makes her angry. In a very weird, Yumi-ish way she cares for her that way (which ofc is tots fucked up and I am not trying to justify it, merely trying to explain it).
I also don't think Chika will be any violent would she ever find out about Sensei and Yumi. Rather she would be happy that finally Yumi found someone she opened up to, sth she didn't even really do for Chika. Ofc, Chika would be incredibly hurt, but she is the kind of person who would accept the pain in favor of Yumis happiness.
However, I fully expect violence if Yumi finds out that Sensei bangs everyone else aside of Chika and Chika finds out that as well and gets hurt by that. THAT is where Yumi would draw the line and that is where she will become violent, because both are family (not by blood but in spirit). Also Yumi would massacre Sensei would he ever hurt Chinamy, but she is the only one safe from Sensei being a creep. Probably. Oh god hopefully...
Rin could actually be in that list as well if Sensei really hurts Futaba, same reason for Yumi/Chika dynamic. Rin is super-chill and attached to Sensei as well but still, that's her red line.
In a weird, similar fashion I'd picture Ayane becoming protective of Sana as well. She would hate herself and Sensei for that, but she would protect Sana over her attachment to Sensei. Not cause she wants but she is genuinely a good person.
That aside, can you guys please not picture my favorite character as the upcoming Star in "Japan Chrime Series"? Would be nice. I am fully aware that she will end in a blender, or she will put everyone else in a blender, but I am willing to pretend otherwise for as long as possible. ^^
Right, Yumi's trying to make Futaba better herself, though she really is going about it the wrong way. I used to count the Futaba bullying against Yumi, but that was before I made the realization she was going about trying to help Futaba in her own weird, violent, bullying way. She's doing things based on what she learned growing up, which was in the tough environment of a yakuza gang. The yakuza don't exactly take it easy on those they see as weak, therefore neither does Yumi.
I also agree on Chika, she doesn't seem like the violent type, but never underestimate the fury of an older sibling. There is one and only one situation where I could see Chika getting violent and that's if Chinami got hurt.
Yumi, on the other hand, WOULD get violent if she found out, especially once she knows he's involved with Chika because then it turns into hurting Chika by cheating on her. Again, a situation where he'd better run far away if he wants to survive. The same can be said if harm comes to Chinami. I honestly don't know which would be worse, Yumi or Chika, because both would hunt him down for allowing Chinami to get hurt and would DEFINITELY murder him if he hurt her himself.
I don't see Rin getting violent under any circumstances except in self defense or defense of another if she witnesses violence in progress. I could see her resuming her self harm or worse if something bad happened to one of the other girls, especially Futaba, Otoha, or Chika.
Ayane, however, yeah, she would get violent in a heartbeat and she knows how to defend herself and others. Those martial arts lessons aren't just for show. However, here is where I see a major conflict. She is obsessed with player Sensei to an extreme level, so the question of if her obsession would win over her common sense, which at that point is screaming at her to save Sana or whoever is in danger, remains unanswered.