Sulk (4)
'sulk' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for mope that I've seen before include "Moon around" , "Hang around being miserable" , "Become gloomy" , "Move listlessly and aimlessly" , "Misery guts" .)
(Other definitions for pout that I've seen before include "show sulkiness" , "Look sullen" , "Push lips out as sign of annoyance" , "Push out the lips (alluringly?)" , "Push lips out in petulance" .)