An epic fail going topless with this woman (7)
I believe the answer is:
abigail
'this woman' is the definition.
'an epic fail going topless' is the wordplay.
'an' becomes 'a'.
'epic' becomes 'big' ('big' can be similar in meaning to 'epic').
'going topless' means to remove the first letter.
'fail' with its first letter taken away is 'ail'.
'a'+'big'+'ail'='ABIGAIL'
'with' acts as a link.
(Other definitions for abigail that I've seen before include "Serving girl" , "Woman's name - old lady's maid" , "domestic" , "Girl's name" , "Lady's maid (once); David's wife (I. Sam.)" .)