Lumpy Space Princess

Space Princess is fully capable of floating, she can still fall accidentally.

Personality
Lumpy Space Princess acts similar to a bratty, apathetic, attention-seeking and willfully ignorant teenager.

Lumpy Space Princess can be ostensibly unmoved and uncaring about what goes on around her, using such words as "sure," "whatever," and "fine" frequently. She can also be physically apathetic and unwilling to make an effort, as shown in "Gotcha!" when she reluctantly helped Finn and Jake carry rocks, but complained the entire time (even though it was only two small rocks).

She prefers to be the center of attention and when people ignore her she will yell things out to regain the spotlight, such as in "The Creeps" when she interrupted Finn by talking about her relationship with Brad. She also became upset (and violent) when another group performed the song she chose during the talent show in "Five Short Graybles," and again when Finn and Jake took the win out from under her.

She often misinterprets things and jumps to conclusions, as shown in "It Came from the Nightosphere" when she saw Hot Dog Princess's soul being sucked into Marceline's dad's mouth, and became upset for not being invited to the "party." She will also create drama where none exists, such as in "The Monster" and "Gotcha!" where she assigns names and personalities to animals and insects in order to act out romance-driven storylines.

She tends to lose her temper and make fun of people, but she can sometimes attempt to be nice towards others. For example, when Jake contracts the lumps she agrees to help and takes Finn and Jake to Lumpy Space for the cure in "Trouble in Lumpy Space." She was also at the hospital, apparently concerned for Princess Bubblegum, in "Mortal Recoil."

Parents
Her strained relationship with her parents is first shown in "Trouble in Lumpy Space" when she has an argument with her parents and they ban her from using the royal car. After the fight Lumpy Space Princess tells Finn that she "lumping hate[s] them," and that her "parents are horrible idiots." Lumpy Space Princess is shown to have run away from her parents and set up camp outside in the woods as of "To Cut a Woman's Hair." She is also seen in "Heat Signature" cooking a can of beans in a makeshift camp. In "The Monster" she explains that, after an argument with her parents, she ran away to the woods and was found by a pack of wolves. The wolves took her in and raised her as one of their own, but she was banished after causing too much drama. She came upon a village, but the villagers mistook her for a monster and ran away. Lumpy Space Princess began using this to her advantage and took up the guise of a monster to scare away the villagers and raid their crops. After talking with Finn and Jake, she realizes her mistake and reconciles with her parents; however, in "Princess Monster Wife" she is once again living at her hobo camp.

Other Lumpy Space People
Her only known Lumpy Space Person friend is Melissa. However, their relationship is tenuous because Melissa is currently dating her ex-boyfriend, Brad. This is illustrated in "Trouble in Lumpy Space" when she tells Finn that there's going to be a lot of romantic tension on their ride because she used to eat chili-cheese fries with Brad. Lumpy Space Princess seems to be aware of how shallow her relationships with her Lumpy Space friends are. In "Trouble in Lumpy Space" she tells Finn that he is supposed to be her friend, unlike the "fake" ones she has there.

Finn
Lumpy Space Princess refers to Finn as a real friend, unlike other lumpy people. She is willing to help Finn, as seen in "Trouble in Lumpy Space" where she helps him get an antidote for Jake. She also shows her friendship in "Gotcha!" by reluctantly helping him carry rocks, and complimenting him on being "hot."

Other princesses
She is friends with Princess Bubblegum, as shown in "Trouble in Lumpy Space" where she is one of the people attending the "Mallow Tea Ceremony." She was also at the hospital for her in "Mortal Recoil," seeming to be concerned. She was also seen to be friends with Hot Dog Princess ("It Came from the Nightosphere," "To Cut a Woman's Hair") and Turtle Princess ("Gotcha!"). She seems to have a good friendship with Turtle Princess, because they speak on the phone to each other a lot in "Gotcha!" and Turtle Princess brings her food to her hobo camp. She also gave her the idea to write a book, (which Lumpy Space Princess did) and Turtle Princess told her she loved it, and published it.

Quotes

 * See Lumpy Space Princess/Quotes

Major appearances

 * "Trouble in Lumpy Space"
 * "Prisoners of Love"
 * "Loyalty to the King"
 * "The Monster"
 * "The Creeps"
 * "From Bad to Worse"
 * "Gotcha!"

Minor appearances

 * "Ricardio the Heart Guy"
 * "Business Time"
 * "What is Life?"
 * "His Hero"
 * "It Came from the Nightosphere"
 * "The Eyes"
 * "Power Animal"
 * "The Other Tarts"
 * "To Cut a Woman's Hair"
 * "Video Makers"
 * "Heat Signature"
 * "Mortal Recoil" (cameo)
 * "The Wand"
 * "Conquest of Cuteness"
 * "Hitman" (picture)
 * "Wizard Battle" (cameo)
 * "Holly Jolly Secrets Part II"
 * "Five Short Graybles"
 * "Princess Monster Wife"
 * "King Worm"
 * "The Lich"

Trivia

 * She is voiced by Pendleton Ward, the creator of Adventure Time, which often misleads people into thinking she is a male.
 * Pendleton Ward admitted that he came up with Lumpy Space Princess's voice by cursing around the office in a valley girl accent.
 * Lumpy Space Princess can barf rainbows, as seen in "The Monster," but it may have been the tree bark she ate.
 * She was the first person on the series to call Princess Bubblegum "PB."
 * Lumpy Space Princess is made out of irradiated stardust, according to Pendleton Ward.
 * She starred in an exclusive video on the Adventure Time Facebook page: "Adventure Time - ONE MILLION FANS!"
 * She has a gender swapped version of herself: Lumpy Space Prince.
 * In the episode "Hitman," Ice King states that she is among his least favorite princesses. Though in "Princess Monster Wife" he stated that he used only the body parts of his favorite princesses, Lumpy Space Princess turned out to be one of the princesses that had a body part removed to make Princess Monster Wife.
 * Pendleton Ward stated that if he had to date any female Adventure Time character, he would date Lumpy Space Princess because she has his voice.
 * She tends to use the word "Lump" in the place where swear words could be used.
 * She has an exosuit named after her in the Cartoon Network game, Project Exonaut.
 * Lumpy Space Princess has a ringtone that is simply Turtle Princess saying, "Hey, girl," repeatedly.
 * There are a couple indications that Lumpy Space Princess is a teenager. In "Trouble in Lumpy Space" she goes to the Promcoming Dance (a weekly event), suggesting that she attends an equivalent to high school. Further proof of this is given in "The Eyes" where Finn and Jake are seen dancing at her Quinceañera which is the celebration of a girl's fifteenth birthday. Though, it is unclear if "Quinceañera" has the same meaning in Lumpy Space.
 * Lumpy Space Princess is the final boss of Adventure Time: Hey Ice King! Why’d you steal our garbage?!!.