Zunk is a childlike entity in a trio of ghosts. They appear to originate from New Jersey, according to the P.K.E. Meter readings taken while they haunted a Conrad's chocolate plant.  The Ghostbusters eventually captured them after a lengthy bust, but they escaped from the Containment Unit. Slug desired revenge and set up a fake paranormal eliminations and investigation business to bankrupt the Ghostbusters. Zunk would act as the ghost haunting a location then his parents would arrive and pretend to capture him.
Slug's scheme began to succeed so he decided to escalate things and seek out an old friend named Turlock. They arrived at an abandoned toy factory in Brooklyn, a known dwelling of Turlock. Instead, Slug awoke and angered a Free Roaming Vapor that turned out to be a Full Magnitude Class 10. It pursued Slug and his family across the Brooklyn Bridge. The Ghostbusters recaptured them and then focused on the Class 10. Zunk was last into the Trap. Zunk and his family were later part of the entities that witnessed the arrival of Egon Spengler into the Containment Unit universe when he was in search of the Ghost of Christmas Future, Ghost of Christmas Past, and Ghost of Christmas Present.
Zunk is very dim-witted. The P.K.E. Meter seemingly confirms this when Egon scans Zunk.  It should be noted that he often has trouble saying complicated words and phrases, including words and phrases that sound tricky to pronounce, but are actually quite simple to say, such as "numero uno" or "the sooner, the better"
Flight: Zunk can fly, as shown in Xmas Marks the Spot
- On Cover A of Ghostbusters Issue #6, a Zunk doll is present on the ground.
- Zunk makes a cameo on a special sketch cover of Ghostbusters #9
- On page nine of Ghostbusters Volume 2 Issue #20, Zunk makes a non-canon cameo in the last panel on the left in the garbage can.
- ↑ Slug (2009). The Real Ghostbusters- Ghosts R Us (1986) (DVD ts. 8:39-8:40). Time Life Entertainment. Slug says: "Move it, Zunk!"
- ↑ Egon Spengler (2009). The Real Ghostbusters- "Ghosts R Us" (1986) (DVD ts. 2:40-2:41). Time Life Entertainment. Egon says: "Possibly New Jersey."
- ↑ Egon Spengler (2009). The Real Ghostbusters- "Ghosts R Us" (1986) (DVD ts. 2:42-2:44). Time Life Entertainment. Egon says: "Almost no intellect reading."
- ↑ Egon Spengler (2009). The Real Ghostbusters- "Ghosts R Us" (1986) (DVD ts. 2:32-2:35). Time Life Entertainment. Egon says: "We have three Class 5 Full Torso Apparitions."