Haunt bad bosses? (6)
I believe the answer is:
obsess
'haunt' is the definition.
(to haunt can mean to cause an obsession)
'bad bosses?' is the wordplay.
'bad' indicates anagramming the letters.
'bosses' with letters rearranged gives 'OBSESS'.
(Other definitions for obsess that I've seen before include "Be constantly preoccupied" , "Preoccupy completely" , "Be constantly talking about" , "Think only" , "Haunt - preoccupy" .)