I think the gridlines might be because it's a demo--definitely the words on your face are. Creators will make the demo "off" in some way so you don't just go around wearing it forever and not buy the actual item that's for sale. Sometimes it's words on your face, sometimes it'll be objects rotating around you like a dizzy cartoon character, etc.
ETA: I see where you said all the demos are off and the gridlines remain. In that case I'm not sure. You might still have a demo worn as your body skin even though it's not on your head, maybe? It won't let you have no skin, so something might have stuck around.