Hedvig Fishtrap is an alter-ego of Squidward who appears in the episode "Sold!"
She is a turquoise octopus who has long, stringy hair made out of the bottom of a mop and wears purple jeans, brown boots with heels, a pink scarf, a blue headband, and a yellow top. She has long eyelashes.
Role in episode
After Squidward plays the electric clarinet for Patrick under the guise of a rockstar, he does not change when he rushes back to SpongeBob's house, and so SpongeBob mistakes him for Hedvig. At first, Squidward is confused but he then catches on, feeds SpongeBob trash, and puts him outside.
Her first name comes from the fact that she is wearing a wig.