After her parents’ divorce, Kotori lives alone with her father, Naoto. Over time, she develops intense feelings for him, wanting to take her mother’s place. Naoto tries to control his own desires but resorts to “papa-katsu” (paid dating) for sexual relief.

Rina, Kotori’s shy and submissive friend, is barely noticeable but maintains a friendly relationship with her. One day, Rina confronts Naoto, appearing semi-nude, showing him her breasts and a phone with recordings of her sexual encounters from paid dates. She threatens to keep it a secret from Kotori if Naoto gives in to her advances, leaving him with no choice but to comply.

“I want to see you again.”

Ignoring Naoto’s words that “this is the last time,” Rina sends him a message—complete with a video of the two of them having sex attached. In a hotel room overlooking the night view, Rina enjoys the skilled tongue of her friend’s dad, feeling like her terrible luck with men might finally be turning around.

Though she says no at first, her friend’s dad always gives in to her selfish requests—and in return, she uses her body to give him a deep, seductive appeal. After pleasuring him thoroughly on the hotel bed, she continues with an enthusiastic blowjob in the car. Even at Naoto’s house, she sneaks around behind Koto’s back, boldly climbing on top of him, bouncing and sucking greedily.

Rina becomes completely addicted to these secret “services” with her friend’s dad, and gradually, she starts sinking deeper into increasingly dangerous situations…