Akuyaku Reijou wa Scenario wo Shiranai: Otome Game no Sekai de Shinjitsu no Koi wo Sagashimasu!

Marie, who has had memories of her past life since she was five years old, finally realizes after enrolling in school that the world she is currently living in is that of her younger sister's favorite otome game! However, she doesn't remember much about the characters or the story of the otome game. Deciding that she doesn't understand anything, she decides to just go for it and aim for a wonderful romance, but she finds herself being liked by the characters she wants to capture, and they're likely to compete with the protagonist for them! (Source: Comic Pixiv, translated)