Rise of Zitboy

In real life, acne is a fairly common thing that people go through, usually when they reach a certain age. It's not uncommon to see pizzafaces left and right in the real world, and no one really makes a big deal out of acne unless it's really noticeable on someone.

The world of fiction, however, didn't seem to get the memo. In fiction, especially shows and movies aimed at kids and teens, any character who develops acne (usually a girl, but there are male examples too) will treat it like it's the end of the world, even if it's just one pimple.

Usually this is used as a plot device when a female character is preparing for a date, school dance or something similar. She is bubbly and excited that she'll finally be going out with the boy of her dreams and knows in her heart that it will be the best day of her life. But then, the night before her plans, she notices in the mirror that she has a huge zit that in many cases resembles a flashing LED light (except for the "flashing" part, of course, unless Rule of Funny is in play), usually right in the middle of her forehead. She will then spend the remainder of her time fretting over the fact that she doesn't have perfect skin and will usually take drastic measures to hide or remove the pimple. Her attempts usually fail and the acne is eventually revealed to her peers, who treat it like some kind of hilarious mutation the likes of which they've never seen.

Often, though, her date will tell her that it doesn't matter to him if she has perfect skin or not, saying she's beautiful just the way she is. If a female character with bad acne succeeds in having it removed, it usually reveals that she was beautiful all along.

With male characters, however, this is usually played completely for laughs and there is no sympathy shown to them by any of the other characters at all.

Strangely, most shows that use this trope depict the character as only having one pimple, with the rest of their face being completely clear. If a show is known for anything supernatural or the protagonist has a vivid imagination, expect the zit to become a speaking sentient creature.

This seems to be becoming a discredited trope these days, as it rarely turns up outside of parody.

Anime and Manga

 * Naota treats the horn he grows in the first episode of FLCL like this.
 * Nitori from Wandering Son has quite the reaction when he starts getting pimples, however it's because he doesn't want to enter puberty.

Comic Books

 * With a name like Zits, acne has come up a fair number of times.
 * FoxTrot Paige panics over zits often enough. There was once a week long story of her trying to cover one up by wearing antlers to match her "red nose".

Literature

 * Exaggerated in Scorpion Shards. Supernatural circumstances result in Tory being covered completely in horrible acne. Even her acne has acne. She is very shunned. And it's not funny.
 * Scary Stories to Tell In The Dark. Book 3. The Red Spot. It's not funny, either.

Live Action TV

 * The subject of an entire episode of The Cosby Show.
 * In Saved By the Bell, acne is only mentioned in the high school setting twice: overall as something to be shunned and avoided at all costs (even considering the cast frets about it a lot but largely doesn't exhibit any), and in one episode when Screech is so overjoyed to get his first zit (as he considers it a rite of adulthood) that he names it.
 * In an episode of The Wonder Years, Kevin gets a zit just several days before a nice girl is supposed to visit his family's home. Kevin doesn't want that zit to be her first impression of him and tries several measures to hide or get rid of it to no avail, including covering it up with a bandage with the excuse that he got into a fight. When the girl and her family finally arrive, it turns out that she has a zit too, and so the whole thing becomes no big deal.
 * My So-Called Life, "The Zit". However, as usual for a Deconstruction, the zit doesn't get very much attention.
 * Wizards of Waverly Place Justin gets a magical zit that talks, and hits on older women. He tries to cover it with a hat with a limited degree of success.
 * Justified in the series 3 episode of Men Behaving Badly, "Cleaning Lady". Tony has signed up with a modelling agency to try and impress Deborah, but a zit ruins his only actual job (despite rubbing his face with a concoction containing caribou's placenta) and he gives up.

Western Animation

 * The trope namer is the title of an episode of Invader Zim, in which Zim gets a giant, pus-filled pimple from having GIR's greasy pizza and bacon soap rubbed on his face. It starts out as a more typical example of this trope, with Zim using acne products (which actually make it worse, since he is an alien) to try and get rid of the blemish... until he discovers that the pimple has hypnotic powers. After GIR draws a face on it with a marker, Zim attaches a toy body to it, names it "Pustulio" and uses it to control the kids at Skool.
 * One episode of Ed, Edd 'n' Eddy deals with Eddy getting a large pimple on the top of his head. He tries to hide it, but the other kids in the cul-de-sac eventually find out and tease him mercilessly. He goes to Rolf, who claims to have a special method of removing zits used in the old country, hoping to get rid of his problem. It works, but with the unfortunate side-effect of shrinking his head in the process.
 * In the Doug episode, "Doug's Big Zit", Doug gets a pimple that makes him too embarrassed to go to Beebe's party. In the end, it turns out that it's a costume party, so he just wears a mask.
 * Johnny Test had an episode involving a new miracle pimple-removing skin cream. Of course this being Johnny Test, the cream has side effects, namely causing all the removed zits to merge together into one creature.
 * In Dave the Barbarian, Candy develops a zit that grows into a huge sentient being... which Candy falls in love with.
 * In Family Guy, Chris gets a pimple that's both sentient and evil.
 * In an episode of Teen Titans, Starfire gets a "pimple" that she frets over and tries to hide until Raven tells her that "everybody gets them". However, the "pimple" begins to grow and she develops more deformities on her body until she becomes grotesquely ugly in appearance, leaving Earth after being laughed at. An alien, however, tells her that these are merely symptoms of her Tamaranian puberty, which climaxes with her transformation into a chrysalis. Said alien then tries to eat her.
 * A similar story occurred in tie-in comic Teen Titans Go with Raven getting a zit that was actually a manifestation of her inner evil, which later emerged as a scaled-down Trigon.
 * In an episode of My Life As a Teenage Robot, Jenny becomes the host of a Cluster robot that slowly transforms her into a mechanical monster. The symptoms begin with bolt-like structures growing on her body, which she treats as pimples and which become huge sources of embarrassment for her.
 * Apparently in the world of Kim Possible, not only does the one zit thing stand, but having to use products to prevent potential acne makes you a freak among your peers.
 * Only cheerleaders.
 * In one episode of The Simpsons, Cletus is dismayed that his show pig has a zit on the day of a county fair competition.
 * An episode of Batman the Brave And The Bold has a deaging Batman freaking out more about this than the more obvious problems as a quick gag. Complete with Gross Up Close-Up.
 * SpongeBob SquarePants treats barnacles the way other shows would treat zits; one episode was this trope for Pearl.
 * In "Aaahh Real Monsters", the episode "Krumm's Pimple" Krumm gets a huge pimple that develops a personality and becomes very popular among the other monsters while causing Krumm to be somewhat ignored. This makes him question if his new friends are only hanging around him for his pimple