Aika returns to her late mother's home, where her stepbrother lives alone. On her way back from visiting her father-in-law's grave, she accidentally witnesses her younger brother and his wife having sex. This fuels her stepbrother's frustration over his brother's inadequacy. The next day, while Aika is napping, he approaches her, boasting, "I can make you climax over and over." Initially resisting, Aika gradually finds herself drawn to his insatiable stamina and undeniable charm. As their emotions and desires intertwine, the bond between them deepens into a passionate affair.