Tooth Decay appeared in "Royal Pudding". He kidnapped the princess, and all the Canadians rose up to try save her. Scott the Dick, Ike Broflovski, Ugly Bob and some Eskimos manage to find the princess. Ike kills Tooth Decay using Bob's ugliness, turning him into stone and saving the princess.
In the kindergarten play, while Ike is off, Kyle Broflovski is forced to play the role of Tooth Decay, and Mr. Mackey isn't pleased by his performance. Making the play was a cathartic experience for Mr. Mackey, who lost his father to Tooth Decay several years ago.
Tooth decay appears as a huge green monster covered in spikes.
- When Tooth Decay sees Ugly Bob's face, it turns to stone, but when Terrance and Phillip see Bob's face in "Terrance and Phillip in Not Without My Anus" they are not affected.
- His death is a parody of the Greek mythological figure Perseus showing the head of Medusa to the kraken turning it to stone.