Konna Hazu Ja Nakatta No Ni

From Fantasyshrine:Ryuzaki is an aloof high school student who likes to seclude himself in the infirmary. This, however, teases the stubborn school doctor, Wataru, to seek out other men to quench his lust—!? Or is this love? They both wonder as they desperately fight with their morals. To do or not to do?