Buttsack is a minor Goblin that attended St. Sebastian to rob the students there. In the bathroom it laced a student's insulin with cocaine because she didn't have any money to steal after wedging her cards into the vent and was captured by Maggie Holt, who took it home and bound it with a metal rune. It was later set free by Padraic to hunt her down, only to be thwarted by Sandra Duchamp and again by Maggie with weapons from the Witch Hunters. He is then bound into service to her and forced to assist in the battle against Barbatorem.
It has loose skin that maintained an appearance and smell like the body parts that were his namesake, and was grotesquely fat for it's three-foot frame, giving it an uneven, ungainly appearance. Its legs were like overstuffed sausages sticking out from the stolen, piss-stained pair of shorts it wore. It was just small enough to evade practitioners, but large enough to bully other goblins into following orders and giving him things.
Buttsack is one of the most clever and vindictive goblins to date, tormenting smaller goblins and humans alike for favors and knowledge. In the span of a single chapter it displayed knowledge about both Faerie and Goblin origins, proved to know how to bypass the standard steel aversion that his kind had, and was going to personally torment a student for not having money for it to steal, which it had done in the past.
Maggie rates it as one of the most malicious and capable goblins she met, more or less randomly targeting people. It can gather other goblins in the area and act as their leader.
- Infiltration Magic: It was capable of turning immaterial enough to catch the wind and diverting the connections of people so they didn't notice it. It didn't work on practitioners.
- Curse Magic: It was capable of casting a single-use curse that made every edible thing the person afflicted viewed as rotten.
- Shield: It has a junkyard shield capable of withstanding Dragon Fire.
- Buttsack is the first Goblin to have a viewpoint in the story.