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The Secret to Losing Weight is Sexercise - Don't Grind Your Pussy...No! ～No!

The main character, who is working as a gym trainer, appears in front of Ayaka, who he had a crush on during his student days...
Ayaka, who is now more beautiful and has bigger breasts than before, does not remember the main character at all, and has joined the gym to lose weight for a trip with her friends.
He is shocked, but starts training, but Ayaka's tight-wearing, sweat-soaked body gets him excited and he rubs her breasts!
He is so excited by Ayaka's tight clothes and sweaty body that he rubs her breasts! Ayaka says, "You're sexually harassing me!" but the protagonist convinces her, "It's special training."
When Ayaka is satisfied with him, the protagonist begins to attack her private parts one after another, calling it training for her! What will happen to Ayaka who continues to be blamed?