Roadkill is a possum.
Well, was a possum.

Then one night some drunk went off the road, splattered his ass across an old indian burial ground, and he rose up and started walkin' around like it was all good.

'Course, now it always smells like the ass end of a dead horse whereever he goes, and occasionally he eye'll glow a dim red... He's not too mean though, just got a bite on him!