Hinata who thinks of her younger brother. In order to fulfill her dream of becoming a regular member of her younger brother in the swimming club, she spends her days being embraced by her advisor Oni-sensei. My virginity was stolen by a teacher! I don't like it anymore and want to end this relationship, but the teacher threatens me and I can't quit... The teacher won't let me put on a rubber band, so I'm afraid I might end up having a baby... Actually, I'm having sex with the teacher. Hinata-chan, who does not refuse strongly because of her feelings, is swallowed by the whirlpool of pleasure. Her forbidden pact continues...
