Girl under topless men? Result! (5)
I believe the answer is:
ensue
'result' is the definition.
(to ensue is to occur or result)
'girl under topless men?' is the wordplay.
'girl' becomes 'sue' (girl's name).
'under' means one lot of letters go next to another.
'topless' means to remove the first letter.
'men' with its initial letter taken away is 'en'.
'sue' after 'en' is 'ENSUE'.
(Other definitions for ensue that I've seen before include "Happen as a result, follow ( 5)" , "Cultivate plants/vegetables" , "Transpire" , "Come to pass" , "Happen or come about as consequence" .)