Lady Rainicorn

Lady Rainicorn is a rainicorn and one of Princess Bubblegum's royal steeds, best friend, and companion. She is also Jake's girlfriend, and sometimes follows Finn and Jake on their adventures. She speaks only Korean, using English only when equipped with a Universal Translator (however, she is shown to have spoken a bit of English in "Lady & Peebles"). Princess Bubblegum and Jake are the only other beings in the Land of Ooo, besides Lady's parents, that are shown to understand Korean. In "Lady & Peebles," Lady revealed that she is pregnant; this was confirmed by Princess Bubblegum. In the episode "Jake the Dad" she becomes a mother to 5 puppies.

Appearance
Lady is a long unicorn-like creature. She has a body with the colors from the rainbow like red, yellow, green, blue, violet and pink. She also has a blonde mane, and big round eyes similar to Jake's. She also has a single white, sharply pointed horn. Her mom has a long body like hers, unlike her father. This means that she inherited her length from her mother, since in the episode "Her Parents" her mother and father don't find it odd that Jake can stretch or is long like the females before they know he is a dog. In "Five More Short Graybles" and in "Up a Tree," Lady sported a "baby bump" around the middle of her body.

Abilities
Lady has the ability to fly, phase through walls, and can use her horn to change the color of anything she wants. In the episode "My Two Favorite People," Lady Rainicorn explains to Finn that she can fly because her body can intercept beams of reflected light from the sun and "dance around" on them. In the same episode, she is shown to live in a stable in the Cotton Candy Forest. Like her parents, she can fire a chromatic light beam from her horn, which seemingly hurts. Also, Lady can stretch longer or shorter as you can see when she lands. She may have limited Stretchy Powers. It is revealed in "The Creeps" that she can phase through walls and carry people while phasing. She can play the viola, like Jake. She also has the power to meld people into her being.

Personality and traits
Lady is laid-back and likes to interact with Jake and Princess Bubblegum. She is considered Princess Bubblegum's companion, like Jake is Finn's companion. She does not speak Korean in the original short; she only makes soft cooing sounds (or, near the beginning, hysterical screaming coos). However, Jake seems to understand what she says when he talks to her. She believes she is smarter than Jake. She may also have a fondness for Power Rings although she seems to have no fingers. Jake calls her "the rowdy queen," saying she'll try anything.

Lady Rainicorn, unlike both of her parents, doesn't wear a Universal Translator. It is worth noting, however, that Lady Rainicorn understands English, but either barely speaks it or chooses not to. This is obvious because of the fact that neither Jake nor Princess Bubblegum speak Korean very often when talking to her.

Jake
On the official website in Lady's description, it says Jake is her boyfriend and that they get along so well because of their common interest in the viola. This relationship began in the short when he and Lady Rainicorn were flirting and sharing interests. At the beginning of "Slumber Party Panic," she is shown being playfully chased by Jake, and later in the episode, they both seem to very much enjoy playing "Seven Minutes in Heaven" (which is a game where two people are locked in a closet together to kiss for 7 minutes). In "My Two Favorite People," Lady recalls a time when she and Jake ran naked through a farmer's field, causing Jake and herself to blush which may indicate some level of intimacy in their relationship. In "My Two Favorite People," Jake is torn between his desires to go adventuring with Finn and hanging out with his girlfriend. Lady later says she loves Jake "because he's an idiot" and that he makes her "feel like a genius." In "Video Makers," Jake gets very jealous when Mr. Cupcake flirts with Lady and becomes violently protective of her. The relationship appears to be rather serious, as he also was worried about his impression on her parents and even went to say he was studying Rainicorn history for their future children, which he did in "Paper Pete" to the point where he was so obsessed that he refused to help or acknowledge Finn's troubles, though he eventually gave up the information having gone way over his head. Lady's mother Ethel referred to Jake as hers and Bob's future son-in-law, hinting that she can see them getting married. In Go With Me, Jake takes her to the movie night and they ended up making out through the whole movie night. In the episode "Burning Low," Jake explains to Finn about "tiers" in relationships and is talking about his relationship with Lady Rainicorn in the process. Jake's implications in the explanation indicate that he is very intimate with Lady. In "Lady & Peebles," Lady reveals in English that she's pregnant. In "Five More Short Graybles" she sports a baby bump on her belly when Jake put his thumb in it making her kiss him. In "Up A Tree" she is with Finn and Jake having a picnic. Later in the episode he takes her home as she kissed him. They have 5 children together.

Princess Bubblegum
Lady is usually seen with or near Princess Bubblegum in the Cotton Candy Forest in the Candy Kingdom. In the "Animated Short," she shows great concern when the princess is abducted by Ice King, and even tried to rescue her from him. She is sometimes described as the princess' pet. In "What Have You Done?," Lady flew the princess to the Ice Kingdom so she could ask for Ice King's help in ending the plague in the Candy Kingdom, and showed great disgust at him when he mistook their pleas for help for flirting. Lady even speaks to him at this time, saying "Verily, you are a creature unworthy even of my lady's disdain." When Lady got injured by the eyes in "Lady & Peebles," Princess Bubblegum showed great concern for her. This shows that they connect and have a deep friendship.

Finn
In the beginning of episode "My Two Favorite People," Lady Rainicorn and Finn's relationship is awkward because of the language barrier. Attempting to fix this, she helps Finn and Jake recover the Universal Translator at the bottom of a lake guarded by Lake Knights. At first, Finn is worried that she is "too sweet" for the deadly adventure, but is quickly impressed by Lady Rainicorn's ability to fight. Finn also finds the translator's 'Old Man' voice option amusing, so he and Lady soon become friends. Jake gets rid of the Universal Translator, but any persistent issues Finn has with understanding Lady Rainicorn have yet to be mentioned.

The Pups
The pups seem to respect her, because they came inside when she called them. Lady obviously cares for them deeply, cooing over them while playing with the pups in the house. She seemed to be aware of the pup's abilities before Jake was too.

Ethel
Ethel Rainicorn is Lady's mother, who appears in "Her Parents." She is very shy to everyone but Jake, Bob, and Lady. She referred to Jake as her and Bob's future son-in-law.

Bob
Bob Rainicorn is married to Ethel, and is Lady's father. Bob appears in "Her Parents," and is very impressed with "Rainicorn" Jake.

Mr. Cupcake
Mr. Cupcake tries to impress Lady Rainicorn by flexing his muscles in front of her in "Video Makers." Although she blushes, she tells Jake not to take it seriously.

Quotes
See Lady Rainicorn/Quotes

Trivia

 * Lady's toy version, as seen in "All the Little People," has a different color scheme than she normally has.
 * In one room of the Princess Bubblegum's castle, there are two pictures of Lady Rainicorn on the wall: One of her upper half, and one of her lower half.
 * Two Rainicorns (both of which look like Lady) appear in the Double Rainbow promo.
 * In the animated short, she spoke in a type of gurgling language instead of in Korean.
 * Other aspects of the Rainicorn people seem to be subtly based on Korean culture and history such as the Korean War, Korean games (i.e. Ethel Rainicorn performs a version of 똥침 "dongchim" on Finn in "Her Parents"), and Korean delicacies.
 * In "The Real You," Princess Bubblegum is seen in the beginning with a yellow t-shirt with a red Rainicorn on it.
 * Lady Rainicorn has a gender-swapped counterpart in the Ice King's fan-fiction: Lord Monochromicorn.
 * Her favorite drink is iced latte as shown in "Video Makers."
 * In "My Two Favorite People" Jake refers to her as "the rowdy queen."
 * In "Apple Thief" Jake cooks Finn traditional Korean food that Lady Rainicorn taught him how to make.
 * Despite being based on a rainbow, Lady Rainicorn's body does not display any orange, but in the animated short she had orange on her body.
 * In "Burning Low," Jake implies that her stomach is 15 feet long.
 * In "Card Wars," it is revealed that Lady Rainicorn used to play Card Wars with Jake, and it made her mad that Jake always won and wanted to do nothing but play it.
 * She can speak some English words, as shown in "Lady & Peebles":"I am pregnant!"
 * As shown in "Lady & Peebles," five small dots and two larger dots appear on the heart monitor. Lady is pregnant, and the five dots indicate her children, who would make their first appearance in "Jake the Dad."
 * Lady has a recurring nightmare about zombies attacking her family. The stress causes her to grind her teeth in her sleep.
 * In "My Two Favorite People," Lady is wearing power rings, even though she does not appear to have any fingers.
 * Lady's colors are in reverse order when compared to a normal rainbow.

Episodes featured
"«" indicates where Lady has a spoken role in the minor appearances. Put in cameo if she does not speak.

Major appearances

 * "Animated Short"
 * "My Two Favorite People"
 * "Her Parents"
 * "Lady & Peebles"
 * "Jake the Dad"

Minor appearances

 * "Slumber Party Panic" «
 * "The Enchiridion!" (cameo)
 * "What Have You Done" «
 * "Power Animal" (cameo)
 * "Go With Me" (cameo)
 * "Video Makers" «
 * "Mortal Folly" (cameo)
 * "The Creeps" «
 * "From Bad to Worse"
 * "Holly Jolly Secrets Part II" (cameo)
 * "Dad's Dungeon" (cameo, in Jake's Imagination)
 * "Dream of Love" (cameo)
 * "King Worm" «
 * "Five More Short Graybles" (cameo)
 * "Up a Tree" «
 * "All the Little People" «

Mentioned and/or drawn

 * "Rainy Day Daydream"
 * "Heat Signature" (Title Card)
 * "Still"
 * "Apple Thief"
 * "No One Can Hear You"
 * "Holly Jolly Secrets Part I"
 * "Paper Pete"
 * "Princess Monster Wife"
 * "Card Wars"
 * "Burning Low"