the result of a sandwhich (usually with mayonnaise) mating with a balloon to create a sandwhich balloon.
unfortunately sandwhich balloons have taken to living underground after several countries governments started hunting them for experimentation, a small child was rumored to see one once, but mistook it for a pokemon.
tiny tim: OMG mummy its a pokemon!
mummy: no timmy thats a sandwhich, or is it a balloon?
tiny tim: ITS A FUCKING POKEMON BITCH!
mummy: timmy! apologise right this minute!
*sandwhich balloon sneaks off*