I was about to close my web browser and smacked myself in the forehead. Black roses. In my experience (mostly East Coast of the US) they're used by a Domme to mark her property. I'm reasonably sure it's strictly a FemDom thing. I've not known any male Dom to use them on his submissives, but I could be wrong. Each has either designed her own or had it drawn to her specs. Some include their name or initials with the design, but most don't.