Kiss x Sis

After his father remarries, Keita Suminoe grows up alongside his older twin stepsisters, Ako and Riko, until the three are inseparable. As they enter their teenage years, the twins’ feelings for Keita become openly romantic, while he keeps trying to maintain a clear boundary between family and romance.

When Keita decides to apply to the same high school his sisters attend, entrance exams become only one source of stress. Ako and Riko constantly compete for his attention, and their parents are surprisingly accepting of the possibility that one of them may eventually marry him. Keita must somehow study, survive the misunderstandings, and keep his chaotic home life under control.