I don't know much about metals but purple tells me you've probably been drinking too much grape juice. Naturally the juice would react with the metal in your body and create the glitter. The fact that you are a vampire and you naturally glitter under sunlight does not help either, but you probably already knew that. I recommend a good rest. I'd also venture to say to stay away from liquids as much as possible as that will tend to give your jizz a bronze rusty look to it.