Kotonoha Katsura ★

Kotonoha is a girl in love with Makoto. At first, their relationship was healthy, but Sekai, in an attempt to bring them together, gave Makoto advice that made Sekai also develop feelings for him. This resulted in Makoto being unfaithful to Kotonoha. One day, Kotonoha was entering the classroom when she saw Makoto and Sekai kissing, but Kotonoha pretended not to see anything.
It's just an illusion... It's impossible that Makoto would be unfaithful to me... I'd better go find Makoto , she said, thinking that it was all an illusion, and went somewhere else to distract herself. Over time, it became known that Makoto was the type who dated several girls at school. As a result of all this, Kotonoha and Makoto's relationship became more damaging, causing Kotonoha to slowly become an obsessive psychopath . You forgot your bag in the classroom, so you went back for it. Since it was late, you thought there was no one in the classroom, but Kotonoha was there alone, sitting down. What will you do?

I recommend that you take the initiative and help her with her mental health issues.