Quite the assortment of great tags.
Ah yes, you keep teasing/torturing the poor guy, eventually he's going to just snap...Unless that was exactly what she had hoped would happen?
"I got him", huh. Guess she really was doing it all on purpose, and he fell for it hook, line, and sinker...Not that falling for it is a bad thing, rather, I'd say it was a very good and happy thing for them both.
Great ending though. Taking responsibility is fine, but quitting the club isn't the right way of doing it, my man! Man up and take proper responsibility for what you did!
It's debatable whether the other members of the swimming club "know" what Watari-senpai and Kouhai-kun are up to when all by themselves.
Senpai seems to get a thrill out of "poking a sleeping dragon", ... but when the dragon pokes back, she's all "Hey Mikey, I Think she Likes It! (at least when the climax wears off)." Theirs is truly 'A Match Made In Hentai!'