Unscrupulous fellow, like Billy Bunter? (4,3)
I believe the answer is:
wide boy
I'm afraid I can't even guess how this answer relates to the clue.
Can you help me to learn more?
(Other definitions for wide boy that I've seen before include "Spiv" , "A rather unscrupulous person" , "petty young criminal" , "Tweedledum, for instance" .)