Might they demolish a nice supper, having spent a penny? (10)
I believe the answer is:
epicureans
'might they' is the definition.
The definition suggests a plural noun which matches the answer.
'demolish a nice supper having spent a penny?' is the wordplay.
I cannot quite understand how this works, but
'a' could be 'an' and 'an' is located in the answer.
'penny?' could be 'p' (short for pence) and 'p' is located in the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Another definition for epicureans that I've seen is " Those who want to enjoy life".)