What does Ba-Dump BaDump mean?

Ba-Dump BaDump meaning in Urban Dictionary

as soon as your a with a woman in a confined room, often after a couple of drinks and she denies your offer of sex. In a last ditch effort, you take your index hand and proceed to place it in her own ass, softly shouting "Ba-Dump!" along the way. Outcomes can vary greatly. Your butt or your backside.