Chiaki Yanagishima works as a software engineer for the host club "Butterfly Kiss", while he lives with Masatsugu, the "King". Their relationship has always been tumultuous. Masatsugu roped Chiaki into his life during his college days as a host, constantly bringing home customers and sleeping with them while Chiaki is there. After years of this, their relationship starts to crack, and Masatsugu only calls on Chiaki when he wants to have sex. Fed up with the relationship, Chiaki finally decides to leave, but will Masatsugu let him?