He was described as having a broad face and a flat, hairless head, four eyes, four arms, and two legs. His eyes were arranged in a diamond pattern.
He became L'oric's familiar.
Greyfrog accompanied Cutter, Felisin Younger, Scillara and Heboric Ghost Hands on their journey to Otataral Island. He communicated telepathically with his travelling companions with the exception of Scillara. It turned out that the reason was her pregnancy. Once she delivered the baby, he also communicated with her and displayed a certain affection for her.
- "The demon’s appetite was voracious, and L'oric admired its single-mindedness, if not its rather untidy approach to eating."
- ―L'oric's thoughts while Greyfrog ate breakfast