Ю Комаи

Сидзуки's younger brother is extremely popular among girls, unlike his relative. He loves and respects his brother, but sometimes teases him when it comes to romantic relationships, though he wishes him happiness. He frequently changes his lovers, as he quickly loses interest in them. Towards the end of the manga, he promised Kotono Hanaki, who was in love with him, that he would accept her feelings if she didn't find someone better than him by the time he turned thirty. It was only after talking to his brother that he realized his words had been interpreted by the impressionable girl as a marriage proposal.