Anythingpertaining with; bum, bums, bumming, bummery, bummers and bummees. That is the UK definition of bum, as in arse (ass)
Julian and Sandy, a right couple of limp wristed bummees popped out late one Sunday evening for a spot of bummage at the local bummery, as they are both quite partial to a bit of bum bumming by the local bum bummers.