Dalliance with a b-blonde? (6)
I believe the answer is:
affair
'dalliance' is the definition.
'with a b-blonde?' is the wordplay.
'with' is a charade indicator (letters next to each other).
'b-blonde?' becomes 'f-fair' ('fair' said with a stammer like 'blonde?' was; similar in meaning).
'a'+'ffair' is 'AFFAIR'.
(Other definitions for affair that I've seen before include "Matter or concern, perhaps of the heart" , "A fling (or something more serious?)" , "A romantic intrigue" , "Liaison or intrigue" , "River dam" .)