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I have a mystery stain on my bed. I got a tattoo a couple years ago on my back from a friend. I've had no problems with it. A couple days ago I woke up and noticed a large purple-ish stain on the sheet and I can't explain how it got there. I actually washed the sheets, put them on the bed, went to sleep, and woke up with the stain. I slept on the other side of the bed the next nigh to see what would happen and there is a fainter stain on that side now. Is it possible that I'm leaking? I never considered that possible, but I have no other explanation....