Couple sharing make-up? (9,5)
I believe the answer is:
identical twins
'sharing make-up?' is the definition.
Although both the answer and 'make-up?' are nouns, they are not in the same form of the noun.
'couple' is the wordplay.
I cannot really see how this works, but
'couple' could be 'twin' (synonyms) and 'twin' 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 identical twins that I've seen is " Certain siblings".)