Following a failed confession to her first love, female high school student Mikoto Ochiai contemplates jumping off the roof of the school building. However, her thoughts are interrupted by the arrival of Jin Haiba, the physics teacher known for being a slacker and the butt of students' jokes. Calmly, he lights a cigarette and asks for an explanation of the events that led her to this precipice. Rather than dissuade her from killing herself, he makes a request—will she enter into a romance with him before she dies? Together, the two gradually ponder why they should keep living and why they should not love each other in earnest.
After being dumped by her boyfriend just before their 100-day anniversary, Ha Yeong meets a college guy named Hyeong Jun, whom she accidentally hits in the face with a can, causing him to scratch his Lexus. He demands she pay him $3000 on the spot, but she escapes, leaving her wallet behind.
Hyeong Jun, not satisfied with this, stalks her, demanding money to pay for his car. Since Ha Yeong is a poor high school student, Hyeong Jun writes up an "Enslavement Agreement" to ensure she pays for the damage to his car. Through this agreement, Ha Yeong finds herself thrown into a nightmarish slave life for 100 days: cleaning his house, running his errands, doing his homework, and even cleaning his car.
By accident, she discovers that the damage to Hyeong Jun's car only costs $10, so she decides to take her revenge. However, before she knows it, Hyeong Jun has shown up at her house as her new tutor! He once again takes advantage of her, but soon, Ha Yeong finds herself falling head over heels for him. But what happens when he drops out of her life just when she needs him most?
Hyeong Jun, not satisfied with this, stalks her, demanding money to pay for his car. Since Ha Yeong is a poor high school student, Hyeong Jun writes up an "Enslavement Agreement" to ensure she pays for the damage to his car. Through this agreement, Ha Yeong finds herself thrown into a nightmarish slave life for 100 days: cleaning his house, running his errands, doing his homework, and even cleaning his car.
By accident, she discovers that the damage to Hyeong Jun's car only costs $10, so she decides to take her revenge. However, before she knows it, Hyeong Jun has shown up at her house as her new tutor! He once again takes advantage of her, but soon, Ha Yeong finds herself falling head over heels for him. But what happens when he drops out of her life just when she needs him most?
