The Aie-Aie is a rat-like creature with a snake's tail that was a beloved pet of Queen Etheldredda.
500 years ago it bit people who Etheldredda disliked, causing a Sickeness to them and in the end, instant death. It also bit Princess Esmeralda's cat, causing its death. It was later captured and killed by Marcellus Pye. Together with ExtraOrdinary Wizard Julius Pike, they trapped it with Etheldredda's spirit inside her life-size official portrait inside a room in the attic, Sealed them in, and that was where they remained for 500 years.
Silas Heap UnSealed the room so he and Augustus Gringe could put his Counter-Feet Colony in it, then ReSeal them in so they don't run away. Once the room had been UnSealed, Queen Etheldredda and her Aie-Aie were free to escape and complete their business in the Living World.
The Aie-Aie bit many people, and ran from fire, so people could be safe at night by always carrying a torch.
It was killed when Queen Etheldredda's portrait was burned down by Spit Fyre's Fyre.
- Esmeralda's cat (bitten; later died)
- The ship's cook on the ship where the Aie-Aie came from
- Many people who displeased Queen Etheldredda in her lifetime
- O. Beetle Beetle (bitten; cured)
- Jenna Heap (almost strangled)
- Ullr (attempted)
- Other people who had to go to the Infirmary
- Physik, Prologue