On drug, sweetheart twirling in shiny coat (6)
I believe the answer is:
enamel
'shiny coat' is the definition.
'enamel' can be an answer for 'coat' (enamel is a kind of coat). I'm not sure about the 'shiny' bit.
'on drug sweetheart twirling' is the wordplay.
'on' is a charade indicator (letters next to each other).
'drug' becomes 'e' (E is another name for ecstasy).
'sweetheart' becomes 'leman' ().
'twirling' says the letters should be written in reverse.
'leman' reversed gives 'namel'.
'e' put next to 'namel' is 'ENAMEL'.
'in' is the link.
Can you help me to learn more?
(Other definitions for enamel that I've seen before include "Hard shiny coating on surface" , "Chopper coating?" , "Coating for a tooth" , "Ale men (anag.)" , "protection for canines?" .)