Topless Victor becomes intimate (5)
I believe the answer is:
inner
'intimate' is the definition.
(both can mean secret or private)
'topless victor' is the wordplay.
'topless' means to remove the first letter.
'victor' becomes 'winner' (synonyms).
'winner' with its initial letter taken away is 'INNER'.
'becomes' acts as a link.
(Other definitions for inner that I've seen before include "Target next to bull" , "may not satisfy this man" , "Hidden" , "Annulus nearest bull" , "Not a bad shot" .)