One day his parents are sick of his bad behavior and run away from home, leaving only a videotape and $100, stating they would come back when Joon-soo got his act together.

Shrugging it off, he decides to just throw a small party with his friends, Ki-seok (Ko Gyoo-pil) and Choon-seung (Choi Jae-hwan), in his empty house.

The note claims the high school senior, Han Joon-soo, is the father of the baby and the mother could not take care of him anymore.

Without anyone to help him, other than Kim Byul (Song Ha-yoon), a smart girl who has a crush on him, Joon-soo resorts to bringing the baby to school and his part-time jobs.

In addition to the theme, Han Joon-soo has a problem with his parents and has a baby; in contrast, Takuya Enoki has the ideal family but is taking care of his younger brother in the place of his deceased mother.