"Kelly's World" is the second segment of the sixty-third episode of Star vs. the Forces of Evil. It premiered on March 31, 2019 alongside "Out of Business", and is the second segment of the seventh episode in the fourth season.
Marco visits Kelly at her house but is feeling down. Posing as a local Woolett, Marco decides to spend time around town with Kelly by heading to the local library to return one of her borrowed books. Along the way, Marco faces one misunderstanding after another with her town's customs and mannerisms. They arrive at the library but are too late on returning it in time resulting in Kelly being forced to have her hair cut off as punishment. Marco challenges the librarian to a fight to defend her, so the fight ensues. Marco and Kelly defeat her and her assistants easily with their combined teamwork and depart together as "breakup buddies" holding hands.
- May 24, 2019 (Southeast Asia)