Boggles are humanoid creatures covered in brown fur. Not much is known about them since only one is briefly seen in the episode "Fu Dog Takes a Walk" in Season 1. They are never mentioned or seen again.
Although covered in fur, Boggles have scruffier beards and manes that stand out in comparison to the rest of their body. This permits them to hide in a crowd of humans more efficiently, especially if they wear clothes covering the rest of their skin. Their nose is shaped like a dog's, and they have pointed ears.
- In Scottish mythology, the Boggle is a ghost or folkloric being that is the equivalent of the bogeyman;
- According to Northern England mythology, the Boggle could be a derivation of the Barghest, a dog-like creature with the power of shapeshifting;
- Apparently, Boggles shed so much that it's even worse than a real dog;
- In "Fu Dog Takes a Walk", the unnamed Boggle adopts a pet Beagle.