Average... that is the term that Tatsumi has been plagued with since childhood and continuing into college, leading him to develop an inferiority complex. In a bid to transform himself, he has taken on the role of a "compulsive kisser" ever since a night of heavy drinking. During a party with his club, Tatsumi's attention is caught by Kuga, one of the most well-liked guys present. Upon Noticing Kuga's gaze, Tatsumi hastily retreats to the bathroom, feeling an unusual self-consciousness, where he unexpectedly encounters Kuga. Eager to escape the uncomfortable atmosphere, Tatsumi heads for the exit, but Kuga halts him with a question: "Why am I the only person you don't kiss?"