Bent on being bad (7)
I believe the answer is:
crooked
'bent' is the definition.
(crooking is a kind of bending)
'being bad' is the wordplay.
I cannot quite see how this works, but
'being' could be 'crook' (crook is a kind of being) and 'crook' is found in the answer.
The remaining letters 'ed' is a valid word which might be clued in a way I don't see.
This may be the basis of clue (or it may be nonsense).
'on' is the link.
Can you help me to learn more?
(Other definitions for crooked that I've seen before include "Criminal" , "Bent; dishonest" , "Misshapen" , "Not straight or aligned" , "Warped" .)