The rule 34 of this game has always gave the shivers.
Full of goatfuckers, furries and closet necros.
It's a pity that a game with such innovative mechanics and a fresh story has to have a fandom (if fandoms are not pathetic enough by themselves) who centers itself in the least interesting characters of the game.
The shipping wars of Undertale is the most disgusting thing for the sickest fucks.
If you want to have nightmares search rule 34 for sans and papirus (the other skeleton) or toriel (the goat).
While not so funny, the fanfics and fangames of Undertale are also a good way to find mentally retarded and twisted individuals with the mind and the personality of a 12 yo who can be mil.ked for greater good.
So yeah, this girl (or dude?) is dime a dozen among Undertale's cancerous fandom.