An altogether more accurate
term for 'bum sex', as there are actually willies
involved in it, as these authors well know. It also undergoes frequent use as a rudey exclamation
of horror, when something very
bad or irritating happens.
'Rachel likes to have willy bum sex with
'Kate has willy bum sex five times
'OH WILLY BUM SEX, i forgot the biscuits :('