He is not a real doctor and you should not let him give you a physical.
Doctor Sanity is the resident “mad scientist” of the Sock Puppets From Hell. Blessed with an unmeasurably high IQ and cursed with a terrifying psychosis that prohibits him from using it for anything good, he is essentially a bad idea factory of terror. He makes Dr. Frankenstein look like Walt Disney.
Able to turn almost anything into something powerfully deadly, Doctor Sanity wields science like a drunken madman armed with a machine gun. Some of his previous work includes making a death-ray out of an old television set and a squirrel-hunting drone crafted from a jar of Skippy peanut butter and some butcher knives. And a nuclear-powered toilet.
Sanity also played a key role in the Sock Puppets escape from Hell and is probably the Puppet that Sam (the human the Sock Puppets live with on Earth) hates the most. Because he did something really, really awful to Sam’s phone. Among other things.
The most striking physical quality of Doctor Sanity is his oversized eyeball. So large that it bulges from his head like some sort of mutant growth, it has no lid and is constantly shifting around, making everyone around him feel even more uncomfortable. Because big eyeballs are creepy as shit.
Sanity wears a long white labcoat over all black clothing. The coat is fireproof which is good because Sanity’s “work” usually results in some sort of exploding fireball. Or mushroom cloud.
It has been rumored that Doctor Sanity’s brain is composed of pure electricity and that Satan himself declared Sanity a threat to the The Kingdom of Hell. But those are probably just rumors.
If you want to read more about Doctor Sanity and his unnatural misadventures, read The Sock Puppets From Hell, the self-published novel by Dan Cheek.