Suspend pet, with a guilty look (7)
I believe the answer is:
hangdog
'with a guilty look' is the definition.
(I've seen this before)
'suspend pet' is the wordplay.
'suspend' becomes 'hang' (I've seen this before).
'pet' becomes 'dog'.
'hang'+'dog'='HANGDOG'
(Other definitions for hangdog that I've seen before include "depressed" , "Shamed (expression)" , "Suspend canine with shamefaced look" , "Looking guiltily dejected" , "Apparently embarrassed" .)