Cain's brother following married woman (5)
I believe the answer is:
mabel
'woman' is the definition.
(I know that Mabel is a female given name)
'cain's brother following married' is the wordplay.
'cain's brother' becomes 'abel' (biblical figure).
'following' means one lot of letters go next to another.
'married' becomes 'm' (abbreviation, e.g. in genealogy).
'abel' put after 'm' is 'MABEL'.
(Other definitions for mabel that I've seen before include "Girl" , "Musical, Mack & --" , "Blame (anag.), lady's name" , "Woman" , "Female name; rhymes with mythic story" .)