What is this yaoi manga ?

It's about two highschool students. One of them wanted to see the other pee but the other didnt let him. Sometime later they had secks, the one with lighter hair was at first the uke but after that one time he was the seme for the other times they did it. There was another event where he tried to trick the other one into believing he was cheating on him with the school's nurse. After seeing the scene, the darker haired one ran away in tears and the one with lighter hair chased after him . That's all I remember.