BILWO Share definition Flag Bed I'd Like (to) Wank On. As the name says, a bed (usually another person's) that somone desires to lie on and masturbate. Hey dawg, hayley's bed was so soft, comfy and hidden away- a total BILWO! BILWO by Baron Von Ironmaggot July 26, 2009 0 0 Get merch Get the BILWO mug. Buy Now — $32.95 See more merch