Star vs. the Forces of Evil Wiki

"Kelly's World" is the twelfth episode of the fourth season of Star vs. the Forces of Evil.

It premiered on March 31, 2019 alongside "Out of Business".


Marco and Kelly risk life and limb to return a library book before it's overdue.


Marco travels to Kelly's home dimension of Woolandia after she invited him in "The Ponyhead Show!" At Kelly's house, he meets Kelly's father and learns that greetings and communication among their species, the Wooletts, is predominantly focused around fighting. Marco is excited to make some food with Kelly like they agreed to do, but Kelly is depressed because her ex-boyfriend Tad keeps calling her. After the battle against Meteora, Tad joined a self-help group and found new purpose in his life, finally moving on from his break-up with Kelly and becoming very self-righteous.

As a result, Kelly feels lost and unfocused, especially since she has errands to do that include returning a book to the library. Marco offers to do errands with Kelly so it won't be boring, and she gives him a Woolett body cover to protect him from any other Wooletts looking to pick a fight. On the way to the library, Marco learns that Wooletts use fighting for everything, even currency. He asks if Woolandia has any dojos for practicing karate; Kelly doesn't know what a dojo is, but she recognizes karate as being very similar to the Woolandian martial art of "wool-hair-do". Using Kelly's library book on wool-hair-do, Marco and Kelly study some Woolandian fighting techniques together, including a fighting style called "Dual Mode" in which two fighters fight side-by-side in perfect synchronization.

Marco and Kelly end up reading together for hours, and when Kelly is annoyed by Tad's constant calls and text messages, Marco suggests blocking his number. Kelly realizes that the library is closing in five minutes, and if her library book is overdue, she'll have to cut off her hair as penalty. She and Marco race to the library, but they arrive a few seconds too late before the book is overdue, and the librarian prepares to cut off Kelly's hair. Still depressed from earlier, Kelly resigns herself to her fate, but Marco objects and challenges the librarian to a fight, with the condition that Kelly be allowed to keep her hair if he wins.

Marco and Kelly team up against the librarian, and when she unleashes an army of hair ninjas, they employ the "Dual Mode" style of wool-hair-do to fend them off, eventually emerging victorious. When Tad calls Kelly again, she admits that even though she wants to move on, she couldn't bring herself to block his number. Marco sympathizes with Kelly's situation, admitting that his feelings for Star are getting in the way of the feelings he's starting to have for Kelly. Kelly blushes and admits she's starting to feel the same way.

Marco and Kelly acknowledge the poor timing of their developing feelings for one another, and Kelly proposes that they be "break-up buddies" so they can help each other get over their old feelings and move on after one of them has a bad break-up. Kelly then kisses Marco on the cheek, and they leave the library while holding hands.


Major characters

Minor characters

Title in other languages

Language Title Translation
Japanese ケリーの世界 Kelly's World
Korean 켈리가 사는 세상 The World Kelly Lives In
Portuguese (Portugal) O Mundo de Kelly Kelly's World
Spanish (Latin America) El mundo de Kelly Kelly's World


View the episode transcript here.


Click here to view the image gallery for Kelly's World.
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Production notes



Revelations and continuity

  • Kelly's home dimension of Woolandia is shown for the first time.
    • Marco follows up on Kelly's invitation to her home that she extended in "The Ponyhead Show!"
  • Since the events of "Conquer", Tad has achieved enlightenment by joining a self-help group, and he has become a "nester" (a living nest for mother birds).
    • Marco previously believed Tad to have died in the battle against Meteora.
  • Marco and Kelly calling each other amazing at the end of the library fight is similar to when Star and Marco first fought together in "Star Comes to Earth".
  • Marco and Kelly reveal that they're developing feelings for each other.
    • They agree to be "break-up buddies" so that they can help each other get over old feelings they have/had for other people.
    • Kelly kisses Marco on the cheek.
  • Kelly is aware that Marco's middle name is Ubaldo.
  • Marco reveals he doesn't know Spanish very well.


  • Marco's line at the beginning of the episode, "That's one small step for Marco," is a reference to the famous quote by Neil Armstrong, "That's one small step for [a] man, one giant leap for mankind."
  • Wool-hair-do may be a play on the Korean martial art of taekwondo.
    • The symbols that appear in both the book and the background of the fight also resemble Korean calligraphy.


  • When Marco is getting the bus tickets, he gets punched in the chest. But when the scene cuts to the inside of the bus, he has a black eye, as if he was punched in the face.