Levi corrupt and morally bad (4)
I believe the answer is:
evil
'morally bad' is the definition.
(I've seen this before)
'levi corrupt' is the wordplay.
'corrupt' indicates anagramming the letters (a corrupted spelling of the word).
'levi' with letters rearranged gives 'EVIL'.
'and' is the link.
(Other definitions for evil that I've seen before include "Live badly for badness" , "Morally wrong" , "Satanic" , "no good in this puzzle" , "Malignant" .)