Help Please

I read this a while back. Uke’s mother marries Seme’s father and they loved together and were a real family. Seme spoiled and treated uke like a younger brother but uke came home from school early one day and caught Seme with another guy. Afterwords the uke was going to college but wanted to move out so his brother suggested they live together which made uke nervous. I can’t really remember the rest But I believe this has a prequel with a student x teacher or junior x senior. But please help (￣∇￣")