Extracurricular is a Korean Drama television series that ran for ten episodes (shorter than most Korean dramas, which are usually 16 or 20 episodes) in 2020. Internationally, it was distributed by Netflix.

Oh Ji-soo is a diligent 18 year old student. He has lived by himself for years after having been abandoned by his parents. He has a job to fund his education and his future... by being a pimp. Ji-soo is running a prostitution service via an app. This app, combined with a voice-disguising application, allows him to run his business completely anonymously, unknown either to his hookers or to Lee Whang-chul, the intimidating old man who acts as a bodyguard/enforcer protecting the prostitutes.

Ji-soo's illegal income ties back to his school life in a couple of ways. Min-hee, one of his classmates, is also one of his prostitutes. She's underage, like several others in Ji-soo's stable of hookers. Min-hee is having PTSD panic attacks after a terrifying incident where she was bound and gagged and nearly murdered by a client. Then there's Gyu-ri, another classmate, and Ji-soo's crush. Gyu-ri is not a hooker, being a child of wealth and privilege, but she resents and despises her controlling parents. When she finds out about Ji-soo's criminal activities, she demands to be included. The story follows these teenagers who commit crimes to earn money and the unpredictable dangers they face because of their actions and choices.

Tropes that apply to the series:

• Almost Kiss: Gyu-ri and Ji-soo have made a narrow escape from Dae-yeol's clutches in episode 9. Having gotten away, they are in hiding, catching their breath. They almost kiss, but a siren in the street outside breaks the mood. (It was an ambulance, not a police car.)
• Bound and Gagged: In the first episode the scary guy who is probably a Serial Killer has bound and gagged one of Ji-soo's hookers and is delivering a frightening lecture about how he is "enlightening someone who sold her soul to capitalism."
• Boyfriend Bluff: To make Ki-tae back off and stop bothering Ji-soo, Gyu-ri tells him that they are dating and calls him her boyfriend much to everyone's (and Ji-soo's) shock. Exaggerated when she makes up a random anniversary date (22 days) and talks about Ji-soo like she has known him for a long time in front of Min-hee.
• Buxom Beauty Standard: Ki-tae is a bully and generally an awful, horrible person, but he can be disarmingly honest sometimes, like when he tells Min-hee that he's dating her because he likes her large breasts. (The other reason is that she spends a lot of money on him, which he also admits.)
• Catapult Nightmare: Episode 10 has a played straight example in which Ji-soo pops awake screaming after he dreams that Min-hee is burying him alive.
• Character Tic: Gyu-ri's stress over her Control Freak parents manifests in her picking at her thumbs, until they bleed.
• Chekhov's Gun: Whang-chul's crappy, ancient, cracked flip phone. It's an Establishing Character Moment but it's also important to the plot, as Ji-soo tells him to get it fixed, which means that Whang-chul is unreachable when Min-hee foolishly goes off on a call despite being told to take the day off.
• Cluster F-Bomb: There isn't a single episode where a character doesn't say fuck/shit at least once. Especially Ki-tae.
• Control Freak: Gyu-ri's parents, who micromanage every aspect of her life, like feeding her gross green juice for breakfast so she keeps a nice figure, or checking her makeup before a meeting with business partners. She hates them and is desperate to rebel, which is why she worms her way into Ji-soo's prostitution business despite not needing the money.
• Creepy Souvenir: It's not completely confirmed that the scary guy in episode 1 is a Serial Killer, but it's implied. He definitely clips locks of hair from the prostitutes he terrorizes and keeps them in his suitcase.
• Electric Torture: Ji-soo uses a stun gun to get his scumbag father to reveal where the money is. Unfortunately, he put it into a scam cryptocurrency, and lost almost everything.
• Faux Affably Evil: Da-yeol, the scary gangster who gets his hooks into Ji-soo and Ji-soo's operation. He likes to cuddle his little dog, or pinch his wife on the cheek, or cheerfully offer Ji-soo fried rice at dinner. He also sets up Dexter-style kill rooms and tells Ji-soo that he'll cut Ji-soo's arm off if he doesn't drop out of school and join Da-yeol's gang.
• Flashback: The beginning of episode 8 reveals how Ji-soo and Whang-chul met, one year earlier: Whang-chug was a homeless man living on the streets when he happened to save Ji-soo from a Gang of Bullies. Ji-soo dropped a contact phone off on Whang-chul's bag soon after.
• Gang of Bullies: Ki-tae leads a group of vicious bullies. Sometimes they just beat people, but when Ji-soo's (fake) relationship with Gyu-ri immunizes him from a beatdown, Ki-tae and his gang launch a campaign of nasty pranks, like dumping shoe polish in Ji-soo's locker or unscrewing the seat to his desk so he falls down.
• How We Got Here: The first scene of the series involves a man scrabbling through a box of discarded batteries looking for one to power a taser. It's soon revealed that this is Ji-soo, who is trying to save Min-hee from a terrifying client.
• Horrible Housing: Ji-soo's apartment is tiny, crowded, and untidy, reflecting his less-than-ideal financial status.
• In-Universe Catharsis: After someone in Ji-soo's class mocks him for getting 48 on an exam and for "acting" all smart when he's just a moron Ji-soo finally retaliates by punching him and letting out a scream then yelling "Fuck! I can't stand this shit".
• Imagine Spot: Gyu-ri fantasizes about killing her overbearing parents with Pretty Little Headshots fired from her mind as her eyes turn red and she says "Pew! Pew!" in an out-of-nowhere scene akin to a horror movie.
• Impairment Shot: Dae-yeol and his goons inject Whang-chul with... something in the fight that ends episode 6. His vision is blurred afterward.
• Karaoke Box: Min-hee takes the other hookers to one in episode 2. She's trying to forget her terrifying brush with death at the hands of a deranged client.
• One-Word Title: The official English title, at least, is just the word Extracurricular. However, the Korean title literally translates to Human Class.
• Outlaw Couple: Played with. Gyu-ri forces him to let her join his illegal business and work together, but when it comes to love... they certainly have lots of sexual tension and act as if they are a couple but the nature of their relationship is too complicated to label.
• Monochrome Past: When Min-hee is thinking in episode 7 about the quasi-paternal relationship between herself and Whang-chul, the flashbacks to their bonding moments are in black and white.
• Mutual Kill: The big fight with Dae-yeol and Whang-chul in episode 9 ends with Dae-yeol stabbing Whang-chul several times, but Whang-chul still having enough strength to beat Dae-yeol to death before he dies himself.
• No Ending: The whole series is left dangling. Ki-tae catches Ji-soo in his apartment, and stabs him in the gut a few times before Gyu-ri shows up and knocks Ki-tae unconscious. A gut-stabbed Ji-soo makes it to the stairwell, leaving a trail of blood, where Gyu-ri finds him. When Detective Lee makes it to the apartment complex, all three—Ki-tae, Gyu-ri, and Ji-soo—are gone. The fourth main character, Min-hee, has been whisked to the hospital after taking a Staircase Tumble, but the series doesn't reveal her fate either.
• Rooftop Confrontation: The massive brawl in the Dae-yeol's karaoke bar/brothel ends with Whang-chul chasing Dae-yeol to the roof. They have a brutal fight that ends in a Mutual Kill.
• Shock Party: Min-hee and Ki-tae's "100 days celebration" party takes a bad turn when Ji-soo trips up and causes the cake to drop to the floor and spoils everyone's mood. Ki-tae then beats the shit out of him for ruining their little party and Minhee tries to stop him but to no avail.
• Shout-Out: This drama makes several references to Western-based media at various points:
  • In episode 6 Dae-yeol and a partner set up a kill room for Tae-rim that is covered in plastic wrap. They say they got the idea from Dexter.
  • One of Ki-Tae's friends, who were discussing Gyu-ri's influential power at school and how difficult it is to mess with her, directly references Game of Thrones:
    Chae-bin: That sounds fucking complicated. What is this, Game of Thrones?
  • This exchange between the video games addict Ki-tae and another classmate, whom he uses to run errands for him, as Ki-tae intimidates him into pranking Ji-soo:
    Ki-Tae: What is the task you must perform today?
    Ki-Tae's classmate: Assassin's Creed.
    Ki-Tae: That's right! Assassination. [spells the word out for emphasis]
• Split-Screen Phone Call: Used a lot in episode 2 after Gyu-ri steals the phone that Ji-soo uses for his criminal activities, calls him on his regular phone with it, and demands a blackmail payment.
• Staircase Tumble: In the last episode, Ji-soo realizes that Min-hee has recorded his confession to her, a confession which implicates Gyu-ri as well. They struggle for the phone and she winds up tumbling down a long flight of stairs. She's whisked off to the hospital, her fate uncertain as the series ends.
• Uptown Girl: The difference in economic status between Ji-soo and Gyu-ri is one of the main themes of the show, as Ji-soo points out their unequal pairing status to her many times. Gyu-ri comes from a wealthy family, wears fancy dresses, frequents fancy cafes where she pays with a credit card, and solves everything with money, whereas Ji-soo wears the same worn-out clothes, is totally unfamiliar with those fancy cafes (he pays with cash), and has to take up odd, illegal jobs to make money.
  Ji-soo: [after Gyu-ri offers money to him] It's so easy for you. You buy everything with money. [...] Do you find it fun? My life looks fucking fun to you, right?
• Wham Line: Dae-yeol is trying to get "Uncle" to work with him. Gyu-ri, who has the "Uncle" phone with the voice distortion, tells him that Uncle isn't interested and will return his money. Dae-yeol tries to talk "Uncle" into a meeting, then says "You speak so well, kid, you sound like an adult!" Thanks to the tracker in the box of money, he knows who she is. His flunky Dugi jumps out and grabs Gyu-ri a second later.
• What Does She See in Him?: Gyu-ri's friends can't understand what she sees in him as they watch him trip and even the scene itself cuts to him falling from a chair and getting his pants ripped (due to a prank). To them and their whole class, he's nothing but an average-looking, nerdy "loser", the complete opposite of Gyu-ri.