This unnamed dog is a golden retriever located in Broward County, Florida.
When Sam ends up stuck in a loop and relives a hundred Tuesdays (courtesy of The Trickster), the dog is one of a few individuals Sam sees regularly.
During one Tuesday, Dean decides to go pet the dog. As with every repeated Tuesday, Dean gets killed, this time by the dog who mauls Dean to death.
The dog is not seen again after this.
- This is one of the few animals aside from Hellhounds to commit murder.