She goes through a series of odd jobs, mainly at a local bookstore, before she gets offered a chance to increase her earnings by becoming a substitute test-taker (an illegal act) for the upcoming entrance examination for Sungkyunkwan, Joseon's highest educational institute.

She gets caught by the upright Lee Sun-joon (Park Yoo-chun), who later acknowledges Yoon-hee's talents, and even encourages her to enroll in the university.

There, she must bear with the endless mischief of upperclassman Gu Yong-ha (Song Joong-ki), put up with the constant mood swings of her rebel roommate Moon Jae-shin (Yoo Ah-in), avoid getting in trouble with the strict student body president Ha In-soo (Jun Tae-soo), and keep her secret from being discovered, all the while trying to hold her growing feelings for Lee Sun-joon at bay.

[25][26] The original soundtrack, which featured Park Yoo-chun's band JYJ, sold 110,000 copies in a couple of weeks.

"[38] For the drama's first anniversary, Korean cable channel QTV (a joint venture between Turner Broadcasting System and JoongAng Ilbo's affiliate, IS Plus) re-edited the series into a two-hour TV movie which aired on September 10, 2011.