Taking in strays is, all in all, an understandable vice. The dips in between their ribs, those large and forlorn eyes, they can help you forget the claws and the teeth and the danger lurking beneath fur. But the habit's a knife edge; your efforts may not be rewarded with kindness (animal instincts aren't discretionary) and you may get bit despite what you've overlooked. A stray doesn't care about pity. All it can know is survival.
These warnings apply to strays of the more human(oid) sort, too.
But what may even more perilous with this type than any drawn blood is what you can get when they grow to trust you. You can earn their undying loyalty...or their love. Either from such a wild thing is a precarious path to go down, if you allow yourself to do it.