Maiku Kamishiro is an orphan who possesses only one memory of his childhood: a photograph showing his house, himself, and his twin sister. Seeking to uncover his past, Maiku moves into his former home. Shortly thereafter, two girls abruptly enter his solitary life. One is his twin sister, while the other is a complete stranger. But which is which? From this point, a complicated give-and-take relationship develops between Maiku and the blue-eyed girls. Discover who is Maiku's true blood relative.