Missy

Hat of Nightmares

An ancient, slightly battered top hat, tied with a fine golden ribbon. It is host to a particularly intelligent Shell Parasite, capable of possessing anyone who puts it on.

Appearance-

Missy takes the form of an old black top hat made of an unidentifiable material somewhere between worn leather and silk, with a golden ribbon tied around its base. The middle of the hat has a large slash across it, that can open to reveal a brilliant golden eye, and several clawed, spider-like legs and tendrils are concealed within the hat. 
If separated from its hat, Missy is indistinguishable from other Shell Parasites. However, it has been inhabiting the hat for so long that this may no longer be possible. 

Sentience-

Missy is intelligent for a parasite, with a limited ability to communicate and form bonds with other creatures. Parasites, especially Shell Parasites, are social creatures by nature, but for one to try to socialize with other creatures is rare. Missy's intelligence is most comparable to an incredibly hostile cat.
As for bonds, Missy is closest with Midnight Fenrir, and by extension his adopted family. She is neutral to others, but will attack at the slightest hint of a threat towards those she protects.

Abilities-

Missy’s most deadly power is to possess other people by latching onto their heads. In this state, she can see through their eyes, and control their bodies completely, even down to involuntary functions like heartbeats. However, she cannot access any power with a mental component, and reading a hosts thoughts or memories is draining and may kick her out of the host.
Those under Missy's control gain her striking golden eyes with slit pupils that cannot be concealed, and will inspire great uneasiness in others. Most species will register something uncanny about a possessed hosts expression and movements, but only Nevians will feel strongly enough to raise suspicion, as they are unusually good at detecting possessions.

I can't explain it. No one can. It's just something that we know. And the moment that I saw... whatever that was, I knew something wasn’t right. It moved like it was used to having more than two legs, and whenever it didn’t think anyone was watching, its face just went... slack. Like a wax puppet with its strings cut. The only life in its face was in its eyes. Those beautiful, horrible eyes.