Please help me find the anime
i‘m looking for an anime/manga. The two MCs are a boy and a girl at school. The girl might be older than the boy and taller. She is a bombshell. I think the parents of one of the MCs are away for work — probably the boy’s — so he either lives with the girl’s family, or they are neighbors and both come and go from each other’s houses. The girl is overprotective of the boy.
There is some sport involved at school. There is a scene where the boy is seduced by, or does something with, the girl’s friend or teammate, who is something like the captain of the team. This happens inside the locker room, and somebody walks in, so they hide in a locker.
The MC girl starts to understand that something is happening — that he is becoming a man — and she gets jealous, so she initially offers herself to help him, but afterward they end up together.
There is also an older guy at school who does something with an exchange student who leaves after the semester and dumps him.
I remember that at some point the boy’s mother finds out about the relationship, and there is some drama about the family business that he needs to take over. At the end, in the future, he is successful and they are married with a kid.