Koibana! Koiseyo Hanabi(2007)

Koibana! Koiseyo Hanabi

Meet Hanabi Marui, our heroine who hates boys more than anything in the world!! When she has to decide which high school to apply to, she does it without giving it any thought - it's going to be an all-girls school! However, life's not always as easy. The school that Hanabi thought would be an all-girls high, turns out to be not only co-ed but also consists of mostly boys! How will Hanabi deal with this situation...?

(Source: OneManga)