Rika had always looked up to her older cousin Mao like a sister since she was little. As they grew older, Rika began confiding in Mao about things she couldn't even tell her parents. Mao, being openly gay since she turned 18, now enjoys both love and sex with same-sex partners. Watching Mao so carefree and happy made Rika increasingly see her as a special person...

りかは従姉妹の真緒のことを小さい時から姉のように慕っていた。年頃になったりかは真緒に親にも言えないような相談をするようになる。真緒は同性愛者で18の時からカミングアウトし今は同性相手に恋愛、セックスを楽しんでいる。そんな真緒を羨ましく思うりかは徐々に真緒を以前より特別な存在として認識し始める…。