Sandy Evil-Cheeks is Sandy's evil twin from the Bikini Bottom 2 universe and only appears in the comic of the same name.
She is identical to Sandy, but different, being a brown squirrel, with a large bushy tail and, a dark brown mohawk, and buck teeth. Her suit is black with a skull instead of an acorn symbol and her shoes are kleets. She has a jetpack too, as seen in the picture.
She first appears at the beginning of the comic where she busts out of the treedome, causing it to start to leak. SpongeBob thinks that it is his Sandy, but he is quickly corrected. Sandy Cheeks sends SpongeBob to Sandy Evil-Cheeks' universe to find her Dimentional Portal Machine, while she catches Sandy Evil-Cheeks and makes sure she doesn't do anything evil.