Naive and awkward Gu-chang is on his seventh year of college, constantly failing job interviews and living off of an allowance from his divorced sister. The almost 30-year-old virgin has never had a girlfriend, or even kissed a girl before. One day, he picks up a wallet at a dining hall and meets its owner: sweet, innocent and bashful Ani. He falls in love with her instantly and the two begin dating. But just when everything seems to be going well, he discovers another side to Ani: she becomes overly aggressive, drinks too much and cusses loudly. He learns that his girlfriend has multiple personality disorder, and that wild and violent Hani is one of her two personalities.
Byun is the village idiot and women constantly ridicule him for his impotence. That is until one day a monk teaches him the power of the never-ending erection! When all the men are sent off to war, Byun is the lone male left to satisfy the unyielding libido of the village harlots.