Adult upset squire (6)
I believe the answer is:
risque
'adult' is the definition.
(I know that adult can be written as risque)
'upset squire' is the wordplay.
'upset' indicates anagramming the letters.
'squire' with letters rearranged gives 'RISQUE'.
(Other definitions for risque that I've seen before include "Slightly indecent in France?" , "Daring" , "Suggestive - naughty" , "Bawdy" , "Mildly indecent" .)