https://www.dmm.co.jp/dc/doujin/-/detail/=/cid=d_641227

[Synopsis]

Muneo, a member of the swimming club, was struggling with his swimming.
When he consulted his senior, Kujo Rinka, about it, she told him, "You're not having enough sex."
While he was taken aback by her incomprehensible words, he responded with sound reasoning, but before he knew it, he was having sex with Kujo.
He cums inside her with all his might.
He ends up doing it without much thought but... he wins the tournament... and is selected to compete in the Inter-High!
"What the senior said... was true."
From then on, Muneo and the senior had sex every day in the clubroom.
Day after day, regardless of place or time...
One day, Muneo was invited to the senior's house, where he was introduced to her old friend, Yuina.
It seems that the senior had told Yuina something.
"I heard that if you have sex... your records will improve..."
Then he was introduced to Yuina's friend, Hiyuri.
Muneo shouts -- "Don't push me! Are you telling me to do it with someone I've just met?"
Apparently, having sex really does improve swimming records.
The sex life of a foursome of men and women, all horny like monkeys, is about to begin...!
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The cover and the tan lines are🔥

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