One of Shougo's friends and a tsundere. She is in love with Shougo and even said she wants to marry him. SpoilerIt's later revealed that she met Shougo when he was recovering from an injury in the hospital and he played with her; they even had a pretend wedding. SpoilerAccording to the Vol. 8 of the novel series, it is revealed by DNA test that she's not actually Shougo's sister - but his cousin. Her family owns a clothing line. Spoiler In the anime, it is revealed that she is Shougo's real sister.