Request prior to topless dance, obliquely (7)
I believe the answer is:
askance
'obliquely' is the definition.
(I've seen this before)
'request prior to topless dance' is the wordplay.
'request' becomes 'ask' ('ask' can be a synonym of 'request').
'prior to' means one lot of letters go next to another.
'topless' means to remove the first letter.
'dance' with its initial letter taken off is 'ance'.
'ask'+'ance'='ASKANCE'
(Other definitions for askance that I've seen before include "Sidelong, look say" , "Indirectly" , "Look like this to show suspicion" , "Suspiciously, with disfavour" , "Sideways, awry" .)