Redditor Kconn04 has an ultraviolet skeletal tattoo on his arm, which shines under a blacklight. He commented on the photos on Reddit by writing:

So if anyone is interested in getting one I just have one thing to say. Mine is almost completely faded by now and you can see a couple of the edges of the bones and that’s it. So be prepared for a couple of touch ups on it. I’ve have it for 5 years now and no health problems… It was just like a normal tattoo except there was no ink so it looked weird. You can’t even tell now, no scars or anything.

Ultraviolet Tattoo