Trouble; pester (6)
I believe the answer is:
hassle
I believe this is a double definition.
'trouble' is the first definition.
(I know that trouble can be written as hassle)
'pester' is the second definition.
(I know that pester is a more specific form of the action bedevil)
(Other definitions for hassle that I've seen before include "Les has (anag) - a great deal of trouble" , "Annoy persistently" , "Informal annoyance or quarrel" , "badger" , "Annoying trouble" .)