Percy is a sentient miniature woolly mammoth, one of the products of a secret cloning project carried out by Kirko of Hereti-Corp under government contract. They threw him out after discovering that he was a smart, dangerous omnivore rather than a dumb herbivore as they had assumed. Percy meets Aylee at Cannibals Anonymous and befriends her, encouraging her to eat more humans. However, when Percy convinces Aylee to kill, cook, and eat a human for Thanksgiving, Torg kicks her out of his house. Realizing that she's been doing wrong, Aylee ends her friendship with Percy. Percy is then beaten up by Bun-bun. He finally returns to redeem himself by leading a herd of cloned mammoths like himself to save Aylee, Riff, and Torg from a cannibal convention which was trying to eat them.
Hereti-Corp subsequently tries to hunt the cloned mammoths back to extinction, but Percy and a few others escape. Percy warns Torg about Hereti-Corp's Cloney project, passing along information given to him by Dr. Schlock (under the pseudonym Chen). He also saves Zoë's life by eating a Hereti-Corp sniper that was targeting her.