Lappen often discribes a dumb person over the internet. You can even use it to insult someone as well.
Usually used by germans, the word 'lappen' made it's way to the english speaking internet as well.
Dude I pwn you, you play worst than a lappen, lul!
Learn to play, you lappen!
a person who looks like a dog, that has long scruff (hair). person usually gets bullied a lot
he looks like lappen
beat the shit out of tyler lappen