Kisakinomiya Chihaya♂

Chihaya is the protagonist who is a boy who transfers to an all-girls school from an all-boys school; He became alienated from his father and he distrust people, especially males. Due to his character and his female looks, he was played a nasty trick by other student in the all-boys school and he truanted the school, and consequently he refused to go to the school. His mother ordered him to enter into the Seio Girls' Academy.
His surname Kisakinomiya is his mother's maiden name in order to enter into the school. His actual surname is Mikado (御門). Mariya and Mizuho are his cousins. He is acquainted with Mizuho. But he doesn't like Mizuho because he has been compared to Mizuho who is excellent; His feeling for Mizuho has changed while he hears episodes in Mizuho's school days.
His grandmother on his mother's side came from Northern Europe and he is gray-haired due to the atavism. He behaves himself like a lady perfectly and he is good at studies and sports. He becomes the focus of attention, and he becomes the seventy-fifth elder sisters with Kaoruko.

[Taken from Wikipedia.]