Hot fish, always stuffed (8)
I believe the answer is:
feverish
'hot' is the definition.
(thesaurus)
'fish always stuffed' is the wordplay.
'always' becomes 'ever' (synonyms).
'stuffed' is an insertion indicator.
'fish' enclosing 'ever' is 'FEVERISH'.
(Other definitions for feverish that I've seen before include "Frenzied" , "Nervously excited" , "Extremely excited" , "Restlessly excited" , "hectic" .)