Hi Hieveryone,
It depends on how thick your sticker is. If the sticker is thick enough to touch the display screen when you close the lid, then yes, over time, you may see some sort of mark left by the sticker on the display. If you don't see any mark on the display after a few days, then the sticker is probably thin enough not to touch the display screen.
Solouki
EDIT: I've seen laptops with a lot of stickers next to the trackpad, so I suspect your machine will be fine.