I guess it's also because of how she plans on having the mc raped by some old guys? And the ml knows about it that is why he planned it that way? It's just my guess tho.
this is exactly why
Also because she was saving her V card for his uncle
better to kill her than rape her.. rape is a strange response.. even for that
Also because she sexually harassed mc and the professor along with the 2 bully lol i'd assume it's not just them maybe they already got a few students raped for money.
I don't think killing her was the goal, it was to torture her and be gone. I also think he used the teacher as his pawn because that saves him from becoming the culprit just like how he did to the fat guy. The one that they would accuse that killed the fatty is going to be the gang AND this time it's the teacher and not him. It's basically using others to your advantage and them doing the work for you and it just so happens that the revenge turned out that way because of how they harassed the teacher before too.
I hate when revenge has rape in it. nothing warrants rape as a response sorry. Just beat her up and disfigure her face or something damn