Beta Couple: Yi Jung and Ga Eul. They could also fit under Ensemble Darkhorse, considering the fact that there is probably more fanfiction written about them than about the two main leads.
Big Fancy House: There are several, predominantly Jun Pyo and Ji Hoo.
Bitch in Sheep's Clothing: Oh Min Ji, Jan Di's best friend at the High School. Lampshaded in that she gives Jan Di a stuffed sheep toy wearing the school uniform.
Jun Pyo: "If sorry was enough, then why would the law and police exist?"
Jae Kyung: "Let's go together!"
Chairman of the Brawl: Jan Di gets a chair smashed on her shoulder during the kidnap episode. The long-term damage means the end of her swimming career.
Color-Coded Characters: Ji Hoo wears white or light colors; Jun Pyo generally wears black, and they both drive vehicles in their preferred colors.
Cool Big Sis: Jun Hee, Jun Pyo's older sister who drives a white Ferrari and is known at school as "The Charisma Queen".
Drowning My Sorrows: Jan Di accidently gets drunk, but still uses the situation to mumble her sorrow over Ji Hoo to Jun Pyo. This starts the transfer of her feelings to Jun Pyo.
Multiple-Choice Past: Is Woo Bin's family the mafia or involved in the construction business? Or both?
Nosebleed: Used in this series to indicate overwork and a general shutdown of the body. It mostly occurs with Jan Di when she is working more than two jobs.
Offscreen Teleportation: In episode 7, Jan Di on her bicycle chases Jun Pyo in the limousine, somehow arriving at the Shin Hwa residence at exactly the same time. Slightly lampshaded: he asks her how the hell she got there.
Operation Jealousy: Yi Jung runs one for Ga Eul's benefit, to get back at her cheating boyfriend. Ji Hoo exploits this by using one, together with Distracted by the Sexy, to win a race against Jun Pyo.
Ji Hoo's horse, given to him by Soo Jin, is named Rui after Hanazawa Rui who is Ji Hoo's counterpart in Hana Yori Dango
There Are No Adults: School children being bullied to suicide, burning bicycles and throwing trash into the school pool, kidnapping, blackmail, etc., yet no adults seem to exist on campus, and there are no consequences.
Time Skip: A six-month skip in the middle of the series, and a four-year skip at the end.
Will Not Be a Victim: Jan Di tries to stand up for herself, even while physically being assaulted by groups of classmates.
Who Would Be Stupid Enough: Almost word for word when Jan Di wonders if Jun Pyo is still going to be waiting for her in freezing weather. After her mother quotes this, she takes off running.
Why Did It Have to Be Snakes?: Jun Pyo is flat-out terrified of bugs, snakes, and swimming. Ji Hoo has a driving phobia.