Fellow and blonde running away (6)
I believe the answer is:
flight
'running away' is the definition.
(flight is a kind of running away)
'fellow and blonde' is the wordplay.
'fellow' becomes 'f' (abbreviation - of a society etc.).
'and' is a charade indicator (letters next to each other).
'blonde' becomes 'light' (I've seen this before).
'f'+'light'='FLIGHT'
(Other definitions for flight that I've seen before include "Aviation" , "Journey by air" , "Fleeing" , "A series of stairs" , "the vanquished may take?" .)