Wipe bum (6)
I believe the answer is:
sponge
This clue is a double definition.
'wipe' is the first definition.
(I know that sponge is a more specific form of the action the wipe)
'bum' is the second definition.
(take money from someone without reciprocating)
(Other definitions for sponge that I've seen before include "Sea animal often found in bathroom" , "that lives in the sea" , "drunkard or > hanger-on" , "mop" , "Sea animal found in bathroom as washing aid" .)