Does it have to e an animal?
Aligator, one who "Aligates" (presumably)
ligated, to ligate (past tense)
ligate, verb (surgery) to tie up or otherwise close off (an artery or vessel)
Not closed of arteries or vessels = bleeding
Aligator - one who leaves people bleeding?
Yeah okay, that's some word hoops to jump through to get to that definition but hey, is pretty cool~