Ayase Saki - Second year in highschool . Because of her mothers's remarriage she becomes Yuuta's younger step sister . Because of her flashy clother she's often believed to be some delinquent , which is why she doesn't fully fit in the class.

Narasaka Maaya - Saki's classmate . Always energetic and meddlesome , she saw the solitary Saki and became her friend through endless bothering.

Asamura Yuuta - Second year in high school . Bacause of his father's remarriage he becomes Saki's older step brother . He's average high school studemt , but he keeps a certain distance to other people . practically addicted to reading books.

Maru Tomokazu - Yuuta's classmate . Probably Yuuta only real friend at school. Member of the basketball club , and an otaku.

Asamura Taichi - Yutta's actual father , and Saki's new step-father . A lot of things happened with his previous wife , which is why they ended up getting a divorce.

Ayase Akiko - Saki's real mother and Yuuta's new step-mother . After her divorce with her previous husband , she focused everything on work and raising Saki on her own .

Yomiuri Shiori - University student , and yuuta's senior at the bookstore he works part-time at. Always interested in other people , and openly supports Yuuta's relationship with Saki.