"I'll find all of your most sensitive spots." Makoto Katsuragi, a man working for an advertising agency, has so far led a perfect private and work life. However, that all comes crashing down in an instant when he loses everything he holds dear. In the midst of his despair, he drunkenly climbs onto the ledge of a tall building and is about to jump, when... "If you're going to throw away your life...let me have it." He is saved by these words offered by the sudden appearance of Ryuji Yoden, and decides to do exactly as Ryuji says. From the moment Makoto awakens in Ryuji's room, his daily life of retraining begins, giving away not only his body, but his heart...