Tartar speaks the truth. It’s all the sluts fault. That’s it.
Are you talking about Sekai? Because in the anime, Kotonoha is no such thing. Unless you’re talking about the game, then, pfft, hell yeah.
In the anime, Sekai led him astray by tempting him with her body and disguising it as “practice” which a girl would never fucking do unless she wanted to like…fuck you or something, despite knowing that he was in a relationship with her own friend. It’s such a slutty thing to do. Kotonoha is made to be her foil. So while Sekai was out there and all slutty, Kotonoha was reserved and quiet and wasn’t comfortable doing anything remotely sexual. The most that she does is suck Makoto’s face off but that’s all the way at like the end in the anime. She’s even raped for crying out loud. But in the game, they both do slutty things. Ahaha.