He is a decrepit old man in ragged clothing.
He is the eternal enemy of tooth fairies everywhere, and seeks to rot the teeth out of everyone's heads so they will be as miserable as he is.
When a rash of children with bad teeth flood dentists' offices everywhere, Funshine Bear and Bedtime Bear go down to investigate, and find that instead of money, the kids are getting "terrible taffy" under their pillows. Going to Grams Bear for advice, she immediately contacts her old college sorority sister, a tooth fairy named Gracie to find out what's going on. Gracie tells her that they have a missing tooth fairy they believe has gone rogue named Fairy Boatride, though he hasn't been seen in some time. Setting a trap by putting one of Baby Tugs' teeth under a pillow, they catch the fairy in the act, but learn that he is under the control of Doctor Decay, enemy of all tooth fairies.
Making their way to Decay's stronghold of Castle Cavity, Funshine, Bedtime, and Good Luck Bear confront the evil doctor, who they learn is transforming all the children's teeth into tiny living tooth creatures called Molites that he plans to use to help spread decay across the world. Using over-sized teeth cleaning instruments like brushes and floss, the bears defeat his Molites and corner the villain, who tells them that he's only evil because he never grew a "sweet tooth" as a child. Fairy Boatride tells him he'll give him a spare if he'll mend his ways, to which the doctor agrees.
|Auntie Freeze - Beast of Boredom - Mr. Beastly - Professor Coldheart - Dr. Fright - Frostbite - Green Creature Slaves - No Heart - Shadows - Shreeky - Sour Sam - Strato Nefarious - The Bull|
|Movies and TV specials|
|Dark Heart - Dim and Dum - Gummy and Rumble - Rat King - The Spirit - The Vizier - The Wizard of Wonderland|
|Alaskan King Crab - Beezy the Sleazy Freezy Dragon - Caretaker - Doctor Decay - Drizzly Bear - Gamester - Gloomies - Glump - Green-Eyed Monster - Haywood the Hailstone Hare - Lunchback of Notre Dame - Mooseter T - Night Mayor - Robert the Robot Litter Basket - Sand Witch - Scare Bear - Slush Monkey - Upside-Down Clown - Who Cares Bears - Winslow Homely|
|Grizzle - Mr. Beaks - New-B - Sergeant Rocketbottom - Sir Funnybone - Phido, Cleon and Bidel - UR-2 - Windle|
|Beasties - King Beastly - Bluster - Bad Crowd|