Kono Inu wa Mada Amai Doku o Shiranai

From xiaojiangworld: As a 3rd year and the sole member of the gardening club, Sakaki is taken care of by Matsumoto during his rehabilitation time until he can go back to being a regular of the baseball club. When Sakaki frees Matsumoto from their master-slave relationship, Matsumoto refuses. The reasonis because he has dirtied Sakaki in his mind countless times.+