Means "I never liked your smile". A popularmemeamong artists, writers and memers, mainly gamers. Originated from the online omori fanbase, hugely popularly among A03 writers.
"yk what? i never liked your smile anyway."
"Huh? You read that fic too?"
"Yeah of the 12 year old asian beat up kid who said INLYS"
when you're holding up your phone and making faces at it, as though you are taking a selfie, but you're really taking a picture of the person across from you or the wall or anything else that seems interesting but you don't want to be caught dead taking a picture of.
This action is often made more convincing by wiggling the eyebrows or opening the mouth, to pretend you're trying to get a Snapchat filter to work.
FRIEND A: "Did you just take a stealthie of me?"
FRIEND B (turning phone around): "no I was just using snapchat's new filter, see?"