A woman finds a man in a box in front of her home and takes him in. She jokingly says she wants to keep him as her pet since the man reminds her childhood dog. The man agrees. Later the woman discovers that the man is a dance prodigy. Complications arise when her old flame from college appears.

After being dumped by her boyfriend just before their 100 day anniversary, Ha-Young, meets a college guy named Hyung-Joon when she accidentally kicks a can that hits him in the face and causes him to scratch his Lexus. He demands she pay him $3000 on the spot. She escapes from him, leaving her wallet behind.Hyung-Joon stalks her, demanding money to pay for his car. Since she is a poor high school student Hyung-Joon writes up a "Enslavement Agreement" for Ha-Young in order to pay for the damage to his car. Ha-Young is thrown into a nightmarish slave life for 100 days, cleaning his house, running his errands, doing his homework and cleaning his car.By accident she finds out that the damage to Hyung-Joon's car only costs $10! She then takes her revenge. However, before she knows it Hyung-Joon shows up at her house as her new tutor! He once again takes advantage of her, but soon Ha-Young finds herself falling head over heels for Hyung-Joon.