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Touching a childhood friend that starts when you take off your clothes! -Practice sex before the real thing with your girlfriend

"If you don't do it properly, I'll be embarrassed..."
--Kenji is worried about having sex with his girlfriend for the first time because he is a virgin.
Kenji's childhood friend, Arizumi, hides her love for him and asks Kenji to be her practice fuck partner.
Every time he touches her, her whole body starts to throb, and even her pussy starts to get itchy, but Kenji attacks her because it's just practice!
Kenji says it's just a practice session and he's going to practice with her so he doesn't make any mistakes.
The love affair between childhood friends who are in the midst of adolescence gradually escalates!?
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Its still cheating, even if its "just for practice"