help please

Looking for a manga.. Not sure if it's a collection or one story. The uke is always in the library and he watches his best friend from the window. The friend is on the baseball team and starts to date the manager. There is a part were the seme goes up to the window and tells the uke to wait for him to change and starts to take his shirt off. Later, the seme tells the uke that all 3 of them are going on a trip and the uke said that would be weird and didn't want to go with him and his girlfriend. The seme doesn't like that cause they always take the trip together.