world isnt real

We know very little of the past of the fallen humans in Undertale. Even Frisk, the main character of the game, has only little confirmed information about them. 

Whilst no official answer has been given regarding their past, there are however a number of clues in the game that seem to point to a certain direction.

Frisk exists as their own individual outside of the player, and in those instances where Frisk acts or talks on their own free will, they leave hints concerning their own personality, likes, dislikes, fears, and what appears to be hints of their past.

Here is something that Frisk asks Gerson on their own after a true pacifist ending.

Tenna art by @9Aaaalt29 on twt

Tenna art by @9Aaaalt29 on twt

Sunny + Orgy Buffets

their (live!) young gestate for. wait for it. eight to eighteen (??) YEARS. can have up to 10 at a time. good grief.

longest lifespan of any vertebrate, up to five hundred years

toxic flesh

has giant eyes but is usually blind because of a weird little crustacean that's evolved to live on and eat their eyes. this doesn't seem to bother them much.

lives in deep cold water and has the lowest swim speed and tail-beat frequency for its size across all fish species. just generally lives life in extreme slow motion

largest genome of any shark

eats everything including moose and polar bears