though it involves spoilers for homestuck, so if you plan on reading it, or haven't read that far, or just care about spoilers don't keep reading.
so in homestuck the in game game Sburb can reset reality into a different state if the session of the game which one is playing is deemed as "destined to fail" (these resets are called scratches). So what i was thinking, is that since Homestuck is already a part of UnAnything cannon, what if a small group of guys from the UnUniverse play Sburb and fuck up, initiating a scratch, creating the UnNothing universe.
also in Homestuck, there are "universal constants" which are things, people, and places, that exist in every possible universe and timeline no matter what.
in homestuck an example would be Will Smith. We could use this to justify the existence of characters and things from the UnAnything cannon in UnNothing. i already had the idea of Vinesauce and the various countries they're responsible for being a universal constant