There's nothing with "cheating" or "netorare" element in the story (except some stupidity of people who can't read Japanese). Just the black-haired girl, who's an actual bitch, had casually called the MC to her action room. Then the blond-haired girl came and reeled him to exchange virginity with her. Still, It wasn't clear yet why the black-haired girl called the MC in the first place. Maybe it will continue, I guess?
https://www.pixiv.net/artworks/115139838 2024年1月14日、インテックス大阪にて開催されます「こみっくトレジャー43」にて頒布いたします新刊「PURITY OR BITCH?」のサンプルです。完成まで長らくお待たせいたしました…。 4号館B-16b「ユウベノ学園祭」よろしくお願いいたします!