KIL-115 - Swimsuit Instructor Humiliation: Twitching and Self-Pleasuring Under Pressure

To summarize: it starts with bathroom voyeurism and turns into something like a rape scene, but the girl gets really into it and they finish with a creampie! Since she's wearing a competitive swimsuit, the act of inserting fingers or a penis feels way more erotic and stimulating than if she were just naked.