Tsukasa is an omega who's in a relationship with his childhood friend Yuusuke. But since Yuusuke is impotent, the man requests that Asahi, an alpha, takes his place. All Tsukasa wants is to be with his first love. Will the two truly be together as one someday?

Niwa Issei lives night to night in the homes of random girls while attending music college. Issei runs into a senior of the composition department, Yui Mahiro, as he makes a girl cry! Even though he is the son of a genius pianist, Yui is in the composition department. Issei, who fell in love with his music, involved Yui in his band for the cultural festival. The usually awkward and unfriendly Yui has a pure, stoic side which Issei finds absolutely endearing.