Twinkling in private room reveals Screwtape, say (5)
I believe the answer is:
demon
'screwtape say' is the definition.
I can't judge whether this defines the answer.
'twinkling in private room' is the wordplay.
'twinkling' becomes 'mo' (both can mean a brief period of time).
'in' indicates putting letters inside.
'private room' becomes 'den' (a secret room or location).
'mo' put inside 'den' is 'DEMON'.
'reveals' acts as a link.
Can you help me to learn more?
(Other definitions for demon that I've seen before include "Evil spirit, devil" , "Imp" , "ace" , "Fiend, devil" , "Genius" .)