Muffin is a fictional animal character featured in the Friday the 13th film series. It made a single appearance in the 1981 sequel, Friday the 13th Part 2. The actual name of the animal is unknown. Muffin is a Shih Tzu that belonged to a camp counselor named Terry. In 1984, Terry went to work for Paul Holt at Packanack Lodge, which was adjacent to the more infamous Camp Crystal Lake. Despite warnings of being in bear country, Terry let Muffin walk about on her own without a leash. Another counselor named Scott, who had a crush on Terry, tried to get in her good graces by "dancing" with Muffin as a segue towards putting the moves on Terry, but she shot him down.
Ultimately, Muffin took off and went missing. While walking through the woods, Muffin came upon legendary serial killer Jason Voorhees. Two other counselors, Jeff and Sandra went exploring over by Crystal Lake and found the massacred remains of a dog. They weren't sure if it was Muffin or not, but were concerned about telling Terry. They decided to keep the information to themselves. That evening, while the other counselors took off for one last night of fun before the work season, Terry elected to stay behind to look for Muffin. Unfortunately for her, what she found instead was Jason Voorhees, who murdered her and brought her back to his cabin in the woods. Muffin turned up later, alive and well, at the cabin of Terry's co-worker, Ginny Field. What became of Muffin following the death of her owner is unknown.