Voyeur, dismal fiancé – essentially, a creep (3-3)
I believe the answer is:
yes man
'creep' is the definition.
(I've seen this before)
'voyeur dismal fiance essentially a' is the wordplay.
I cannot really understand how this works, but
'a' could be 'an' and 'an' is found within the answer.
This may be the basis of clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for yes man that I've seen before include "A male sycophant" , "He always agrees with everything" , "He's unquestioningly obedient" , "Sycophant of assenting kind" , "Affirmative kind of sycophant" .)