Noun: Someone who likes to yiff; to yiff frequently
Matt is such a yiffer.
(Yiffer)Pronounced (Y-I-ph-r)-see (Furry) Slang for Furry. Basically Yiffers are hardcore furrys who dress up in animal costumes and have orgys. Yiffers have an unhealthy obsession with human like animals and have massive "Fur Conventions" and Furry Hentai websites. It is common for them to display animal characteristics. In many cases Yiffers think they are an animal like a fox or wolf, trapped in a human body.
*Not to be confused with beastuality.... but both equally screwed up
That guys a Yiffer! He just growled at me!
Agree used as an inverse of Differ in the term I beg to differ
Guy One-"That's cool"
Guy Two-"I beg to yiffer"
A sad excuse for a human being or beings, that would be deemed pitiful, otherwise normally freakish, if it weren't for their afinity to mate with species other than their own kind.
As the yiffer was housesitting a friend's house, so the buddy can run errands, he cut a hole into the friend's teddy bear, f'd it, placed it back on the shelf and pretended that nothing happened when the friend returned.