The series follows Yui, a shy girl who gets entangled with her promiscuous friend Rina in a world of casual sex and partner swapping. Initially hesitant, Yui is coaxed into her first threesome, where she's double-penetrated by two eager guys. This encounter awakens a deep-seated nymphomania, and she eagerly dives into a series of increasingly intense sexual escapades. Throughout the episodes, Yui and Rina engage in numerous orgies, exploring everything from deep throating and creampies to intense group sex scenes. They get relentlessly fucked in every position imaginable, their bodies used as cum dumps by multiple men at once. The animation focuses on detailed depictions of penetration, overflowing bodily fluids, and ahegao expressions as the girls are pushed to their absolute sexual limits, embracing their new lives as insatiable sluts.