I'm not entirely sure where to put this, but here it'll be for now. Over the halloween period, one of our admins had these blood red gel cling things that stuck to windows and walls. Somebody (I'm nearly certain I know who) decided to stick one that was the shape of a hand on my office ceiling, and for the last month it was lol and all, but when I finally took it off I see it seaped red stain right into the tile:
