Zippers (ファスナー, Fasunā) are creatures that serve either angels or demons as their pets/guard dogs and personal messengers from Heaven or Hell.
Description
They are seemingly a race that are meant to serve angels and demons, or, at the very least, act like their guard dogs and servants.
In the case of Chuck and Fastener, they are almost seen exclusively being bossed around and bullied by the Anarchy and Daemon Sisters, while being tasked with household chores, taking over with driving their cars, and being makeshift mailboxes from either Heaven or Hell.
Culture
Not much is known about the culture of zippers, except that they also have an education system similar to those of humans, angels, and demons. They have their own school dedicated to their species that also functions with a similar social hierarchy.
Biology
Zippers are dog-like creatures that look like stuff toys with zippers sewn on their bodies. They also have small demons living inside their heads, and seem to not be aware of them.
Demons that live inside zippers.
For example, when Chuck first discovered the person living in his head, he was startled and tried getting rid of him.
Zippers and their inhabitants are able to live without one another, as seen when Chuck and his demon person were stuck in a microwave in the episode "Chuck to the Future".
Despite being dog-like in nature, they come in a variety of designs, some of which, like Fastener, resemble the generic alien but with insect/mantis-like limbs, while others may closely resemble stuffed toys, while the zippers on their bodies resemble hair, ears, antennaes, or tails.
While they are shown to share the generic organs of the average mammal, the only difference is that the color of their blood is shown to be a light purple.
In terms of their diet, they are shown to be omnivores and can eat both pet food and human food with no problem.
Chuck is shown eating pet food in "Nothing to Room", and both Chuck and Fastener seem to have an appetite for Panty's severed tongues in "Fa Fa F*ck". Chuck has also shown interest in human foods such as Garterbelt's cooking or the sandwiches Stocking has made for Patrick Fagry. At the end of "Heaven Wars 3 - Revenge of the Bitch", both Chuck and Fastener are seen happily eating ice cream.
Reproduction
Not much is known on how zippers reproduce, but it is hinted that they do so similarly to angels, demons, humans, as well as other mammalian creatures - as they have the sexual organs and desires to do so.
Mortality
Zippers are seemingly immortal to some degree. Like angels and demons, they have enhanced endurance, but even moreso than the former two species.
Zippers can sustain any and every sort of lethal damage, even those that would seemingly kill other mortal creatures, and heal from said injuries in a short period of time.
Despite being indestructible in a sense, they can still get sick from regular means such as food poisoning, as shown in "Being Chuck Maldehole" when he ends up vomiting from eating an expired banana to the point where he dehydrates his whole body of its fluids.
Abilities
They are shown to be almost immortal, being able to regenerate fatal injuries even if their bodies get dismembered. However, zippers enter a paralyzed state if they are ever unzipped.
Their true forms can only be revealed when they are zipped inside out, and, depending on the zipper creature and the circumstances, these forms may vary.
Zippers can also fuse with each other in their true forms with the help of angelic technological enhancements provided by Gunsmith Bitch.
Notable Zippers
Trivia
- As revealed in the episode "Heaven Wars Episode Two - Attack of the Uncle", the reason why the Poly Brothers don't have a zipper dog paralleling that of their cousins' (Chuck) and of the Daemon Sisters' (Fastener) was because they were too afraid to ask their father to begin with, but had always wanted a dog.
- In the Neverending Streaming covering the three-parter Heaven Wars arc, the writers reveal there is an unspecified reason why Fastener and the Demon Sisters' eyes started glowing red when the King of Hell grabs Panty and Brief down with him.
- The zipper species being able to say only their own name might be a reference to how most Pokémon do so in the titular anime.


