you mean the icons or the ones where they eat others?

Icons, characters, etc

i got no clue why they so popular now.

Tail vore

Don't ask me why

Chimeras are often depicted as having a snake for a tail, head/mouth and all...if it's not that then I have no clue o ^o

OM. NOM. NOM.

I think it's an icon fad.

Dunno. If I had an unusual tail I'd make my tail have a paw instead.

nah it's not an icon fad.
it's a species that someone created, that is if you're talking about the cat boys (or from what I've seen most were boys) with the large fluffy tails that had mouths.

but yeeaaa, It's just a species. I've seen em tooo. http://www.furaffinity.net/view/4145591/
if this is what you're talking about x3