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A Beast for a Summer. ～You should resist, right?

"You see that? My fingers are soaking wet from you."
My defenseless swimsuit was untied, and I climaxed for the first time with no escape... I couldn't stand anymore...
Mihiro starts working part-time at a beach house, where she bumps into Satoru, who is in the same class as her, surfing.
He is cool, but a little scary... but she is thrilled to see his unusual behavior,
But just as she took the trouble to show him to her part-time job, he changed completely!
Without knowing why, Mihiro is taken into a private shower room.
Mihiro is taken into the private shower room, where a forceful finger goes deep inside her... What should she do, even though there are other people next door?

English Webtoon version: https://comiko.net/series/78049/one-summer-hunk