They fuck. She leaves to become a better women for him. But she also leaves behind a note, that's highly misunderstandable. That leaves him heartbroken with the impression he's not man enough for her? (He was an unloved hikikomori, with trust issues, and that was his first time.) Wow....Somebody will be crushed, when she returns to see, that he's been taken and she's responsible for quite a bad time in his live.