That is the 'standard' internet symbol denoting a "troll". That is the "trollface". As one is engaging in the act of trolling, that is presumably how one's face looks.
“Everybody has a secret world inside of them. All of the people of the world, I mean everybody. No matter how dull and boring they are on the outside, inside
them they've all got unimaginable, magnificent, wonderful, stupid, amazing worlds. Not just one world. Hundreds of them. Thousands maybe.” -Neil Gaiman