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Drunken sex while watching porn together! ～I was fondling my sister's friend's breasts in the dark, thinking they were my her friend, but they were actually my sister's~

Hey...keep going...do it again?"
――That's what Kotono, a female college student, mutters under her breath.
She invites him to watch a DVD with her, and her younger brother Kotaro decides to attend in order to see his friend Ayane.
Kotono gets drunk and pushes her tits against Ayane's, and while blushing, he sets the DVD on the screen...
"Ah...oh...that's good...there..." and the AV of Kotaro's favorite started playing!!?
Koutarou panics when he unexpectedly watches an AV, but in a pinch, he takes advantage of the opportunity and the darkness and comes up with a prank on Ayane!
When I felt a soft texture and rubbed it, I heard a voice I had heard before, saying, “…nnnnn… yay!”
Even if I think I made a big mistake, it's already too late!! My sister's boobs!!?

An accidental love incident between the members of the drinking, noisy, and relaxed film research club and Kotaro!!
I can't believe my sister is pampering me with such a cute voice! I have no choice but to fuck her!!!