Yuika's older brother. A member of the idol group BOYNEXTDOOR. Height: 174cm. He is not good with scary things. He has a sweet tooth. He doesn't see Yuika very often. At most, they meet about three times a year. RIWOO dotes on Yuika so much that he constantly brags about her to his fellow members.

The members of BOYNEXTDOOR: SUNGHO RIWOO JAEHYUN TAESAN LEEHAN WOONHAK

RIWOO's younger sister. A second-year high school student. Height: 160cm. She loves cooking. A total genius, cute, with excellent athletic nerves and a great physique. Unlike RIWOO, she isn't afraid of anything. Yuika knows about BOYNEXTDOOR. Her personality might not resemble RIWOO's very much.