Kikkake wa Sasainakoto

Mayu, a high school girl, overslept and came to school in her swimsuit to make it in time for the first swimming class. However, she forgot her underwear and had to go without a bra or panties that day. Mayu found pleasure in coming to school without underwear and began to masturbate in secret on campus, but then three male students came into a classroom where no one was supposed to be...!?

(Source: Mujin Comics, translated)

Note: Published in Comic Mugen Tensei 2023-08