The Mob in an Otome Game Has Poison

My job hunting activities ended safely, and on my way home from the station with a cake as a souvenir, I stepped off a staircase and died. For some reason, I ended up reincarnating into the world of an otome game that my younger sister was obsessed with. As I grew up without knowing who I was in my previous life, I happened to meet a girl and became her friend. The moment that happened, I lost consciousness, and when I woke up next, I remembered everything and fell into deep distress. After all, the girl who triggered my memory recovery turned out to be the villain heroine who would obstruct the protagonist at the academy where the story takes place in the future. Of course, unable to bear watching her meet a tragic end, I couldn't help but support her, and she was supposed to walk a path away from being a villain. However, due to the "protagonist" who also reincarnated in this world, she was forcibly branded as the villain heroine. All for the sake of events, forced upon her... I swear revenge on the protagonist. After all, it is my role as her friend.