Affectedly sweet or cute (4)
I believe the answer is:
twee
I believe this clue is a double definition.
'affectedly sweet' is the first definition.
(I've seen this before)
'cute' is the second definition.
(twee can mean cute or pretty)
(Other definitions for twee that I've seen before include "Sickly sweet" , "Sentimentally pretty" , "Affected quaint" , "Mawkish" , "Overly sentimental or pretty" .)