To WUB FAP means to be overly excited over dub step music it causes you to wank consistently in time with the music.
"Dude this music hits the spot! I love this so much! I'm going to WUB FAP this!"

or

(in a night club)
"IM WUB FAPPING THE SHIT OUT OF THIS MUSIC!!"
by Lilly&Claire October 26, 2011
Get the Wub Fap mug.