My husband isn't into pain, so I'm purposely gentle. I've almost never left scratch marks. He's pretty safe from my claws because I don't really have much of an urge to use them.
I am a biter, though, and
that urge is
very hard to resist. I tend to bite necks, ears, shoulders, and lips (NOT cock).

But I usually don't bite hard enough to leave marks, so it must not be
that bad.
For me, at least, teeth add another element to the tactile experience of a man's mouth on my skin. Soft lips, wicked tongue, stubble, and being bitten make for a
devastating combination.
I've had to teach TM to bite me. (That sounds kinda funny!)
I think maybe he just tolerates my biting him...he's not that into it but he goes along with it for my sake.