Harass creature (6)
I believe the answer is:
badger
I believe this clue is a double definition.
'harass' is the first definition.
(synonyms)
'creature' is the second definition.
(I've seen this before)
(Other definitions for badger that I've seen before include "A mammal; harry" , "Disturb" , "Torment" , "Repeatedly ask (someone) to do something" , "One of the weasel family" .)