Harry’s husband, plump, no Romeo (5)
I believe the answer is:
hound
'harry's' is the definition.
(both can mean to harass)
'husband plump no romeo' is the wordplay.
'husband' becomes 'h'.
'plump' becomes 'round' (I've seen this before).
'no' is a deletion indicator.
'romeo' becomes 'R' (phonetic alphabet: alpha, bravo, charlie etc.).
'round' with 'r' removed is 'ound'.
'h'+'ound'='HOUND'
(Other definitions for hound that I've seen before include "despicable person" , "Harry" , "part of hunt" , "Breed of dog used for hunting" , "despicable creature" .)