The scabs and patches of dead skin resembling carpet burns that appear on your penis after excessive wanking.
Guy 1- "Dude, yesterday I tried showering, but the soap stung my doodle so much."
Guy 2- "Oh yeah? Weird... why is that?"
Guy 1- "I got bored over the weekend and got fap burn after jerking off so much.
Guy 2- "Too much info there, buddy.."