Lemon Head is one of the many Lemon Children that the Earl of Lemongrab and his clone create using the candy life formula. He first appears in "All Your Fault," in which he sits in the room containing Lemonjon's kidneys and shrieks at Finn and Jake until his face peels. In "Too Old," he rings the dinner bell and later waves goodbye to Finn and Princess Bubblegum.
- For some reason when Lemon Head is alone in the room there's a screw nearby him. This seems to suggest that he may have been born without a mouth, and used the screw to create one, consequently causing them to shriek in pain.