Kotarou is a beautiful boy. Since his parents divorced, he lived with his mother. But she passed away suddenly and he came back to his house where he used to live. After an interval of five years, he comes back to his house but his sisters, Tobari and Akane, are so cold to him. After six months, Kotarou enjoys his school life with his friends and classmates. But Tobari never smiles in front of him. He tries to make friends with her, but she never smiles until "that" night...