Starting with a Kiss Vol. 2 (manga)

As Tohru and Mutsumi continue their secret affair, Tohru realizes the more they sleep together the more he gives in to the pleasure. And not wanting his lover to play the field, Mutsumi goes out of his way to keep Tohru satisfied. Unfortunately for these two, the very last person they’d want finding out about their secret relationship does. Enraged that Mutsumi would dare lay a hand on his precious charge, Domoto kidnaps Mutsumi with bloody retribution in mind!