Junai Seichouki

Kazuya and Nozomi are so intimate best friends that they enjoy jacking off each other. Kazuya has been hesitant to be uke but on the day he finally decides to accept Nozomi, Kazuya's father sees them making love and decides to separate them by entering his son into the residential high school. The president of the school is Sakuragi who was a junior member at the rugby club when they were high school students. But Eiichi, Kazuya's roommate, will train him sexually to be "a good seme"... (From mangaupdates)