At 14 years old, Luan is the fourth-oldest child of the Loud family, and the second-youngest of Lincoln's five older sisters. Luan attends Royal Woods Middle School. Her habits include telling bad jokes and puns, as well as pulling pranks.
According to "Funny Business", she got narcissistic and cocky when she got her first big laugh, just like Lincoln in the same episode.
Luan is a very goofy and fun-loving girl with a fondness for comedy and making puns. She loves pulling pranks on her siblings, and frequently makes puns for every situation, though she gets on everyone's nerves because of it.
She has a taste for everything that is related to comedy - this includes comedy movies and TV series, clowns, pranks, and funny internet videos. She also likes to record people experiencing funny situations with her camera, but when she does this, she asks permission to the person she recorded to allow her to upload the video to the Internet. Luan already knows that she cannot upload videos without permission from the person who she records in her camera.
Though Luan is typically one of the kinder siblings, she is unstoppable at pranking, particularly on April Fools Day. When April Fools Day comes, Luan becomes ruthless and crazier than ever to the points of being downright evil and psychotic. During this day, her pranks can be even more dangerous than before like in "April Fools Rules", where she placed in every corner of the house pitfalls, transforming the entire house in a lethal trap. This is the only time of the year where Luan is thoughtless and cruel with her siblings, even Lily, and even with her parents. In "Fool's Paradise", after her family made Luan taste her own medicine, she promised the next April Fools will be even worse than before.
She always has a positive and cheerful attitude. She is very optimistic, as she likes to support her siblings, and especially make them laugh and feel better. In some occasions she can get angry when something "not funny", or annoying happens to her, or her siblings; like in "The Sweet Spot", where she fights against the others to obtain the best seat of Vanzilla, "It's a Loud, Loud, Loud, Loud, House", when Luan and the others destroyed the whole house looking for money, or "Brawl in the Family", where Luan and the others argue. No matter how bad the problem is, she'll find the funny side of the matter.
"Luan Loud loves to make people laugh. From whoopee cushions, to squirting flowers, to her ventriloquist dummy Mr. Coconuts, Luan is ALWAYS ready for the perfect prank. One thing's for sure...nothing gets this Loud down!"
Luan has prominent buck teeth, which sport braces on her upper and lower teeth, and light brown hair worn up in a large ponytail by a yellow scrunchie, with two long protruding hairs sticking out from the center of her forehead.
She dresses in a white sleeveless shirt, a yellow skirt with a checkerboard pattern, yellow socks with a line pattern that are worn all the way up, and brown shoes. She also wears three pink flowers, one on her shirt, and one on each shoe, that serve as gag squirt-flowers. Her prototype design had a gag flower on her skirt, but none on her shoes. She also didn't have any braces.
Her swimsuit is a yellow one piece with one of her gag-squirt flowers. Her nightwear is just a yellow nightgown, or a yellow and white nightshirt with matching pants and bunny slippers, sometimes she also wears a yellow bathrobe.
In "Hand-Me-Downer", it is revealed that she has been wearing her braces from her younger age. Back then, she wore a sleeveless yellow dress with a square pattern, a black belt, white socks, and brown shoes.
Luan's flower is a gag squirt flower that she wears in every episode she appears in. Luan owns three of these flowers, one is on her shirt, and the other two are on her shoes. Although only shown twice, these gag flowers are filled with water. Even if she fills these flowers with water, she likes to wear them for decoration.
Outside of the original pilot short, the only time she has used her gag flowers was in "Linc or Swim", when she tried to cool herself off in front of the freezer before finding out about Lincoln's new pool.
Luan's gag glasses are black glasses, with eyebrows, and a nose and mustache at the end of them, which are a reference to Groucho Marx, of The Marx Brothers. They seem to double as reading glasses.
In an alternate universe where the sisters are brothers, Luan is a boy, Lane. Like Luan, Lane is a comedian who tells bad jokes to lighten the situation. However, he acts disrespectful toward Lincoln, mocking him when Luke (Luna) uses him to clean the toilet, when Leon (Lily) bites his thumb instead of kissing it, and when they tease him about Ronnie Anne. He also plays keep-away with Lincoln's time watch to stop him from going back to his own dimension.
In another alternate dimension where he is the brother to a female version of Lincoln named Linka, he is shown to be deeply caring of her.
Lane eventually turns out to be a product of Lincoln's imagination as it was revealed the entire adventure was a dream.
This version of Luan has a female version of her dummy Mr. Coconuts, named Mrs. Coconuts.
In the minicomic "Deuces Wild!", Luan interprets the superheroine called The Joker, who is also one of Ace Savvy's sidekicks. Her powers are not shown, as she's only seen mocking the gas monster. In the comic, she is summoned by Savvy (played by Lincoln) alongside the rest of Savvy's deck (played by the rest of her sisters) to help him and One-Eyed Jack (played by Clyde) to defeat the gas monster. After they defeat it, they prepared to fight against a garbage monster.
The Joker also made an appearance in "Pulp Friction". In her appearance there, she used a jack-in-the-box-like gadget to defeat Wild Card Willy by having it spring under his feet, which threw him across the warehouse they were in.
Luan is a male name in Brazil. A good example of this is singer, Luan Santana.
It is revealed in "Sleuth or Consequences", that Luan records herself sleeping, in case she tells a joke in her sleep.
Luan seems to be interested in magician's tricks:
She has a rabbit living in a top hat.
Her Christmas gift was magician stuff.
She freed herself from a cage like Houdini.
A running gag in the series is that Luan always tells bad jokes, much to her siblings' annoyance.
It is strongly implied she inherited her sense of humor from her father.
In "Making the Case", it is revealed that Luan has her own comedy-themed website. It is also revealed that she has several tapes of Lincoln's past. She explains that it is wrong to upload video footage of others without their permission.
In that same episode, Luan says the biggest rule when making a video is to always keep your camera running.
Her hair is the lightest shade of brown of the brunette sisters. In contrast, Luna's hair is the darkest shade of brown, followed by Lynn's and Lisa's brunette hair, which is slightly darker than Luan's.