Four thumbs

When you type so fast it looks like you have 4 thumbs
Like in anime/manga, they put multiple fingers to show the speed of the characters typing (with an addition of movement symbols like "《" "//" "=" ect...)

Person 1: typing
Person 2: "do you have Four thumbs or summ"

LOL

Acronym for "Lots of loli"

1: Holy shit man that's LOL
2: yeah, that's why I'm not part of the fandom