Abscond in hot air balloon, following female (4,3)
I believe the answer is:
bunk off
'abscond' is the definition.
(I know that abscond can be written as bunk off)
'hot air balloon following female' is the wordplay.
'hot air' becomes 'bunk' (both can mean rubbish).
'balloon' becomes 'O' (O resembles a balloon).
'following' becomes 'f.' (used when citing page numbers etc).
'female' becomes 'f' (common abbreviation).
'bunk'+'o'+'f'+'f'='BUNK OFF'
'in' acts as a link.
(Other definitions for bunk off that I've seen before include "Play truant" , "Abscond (from school)" .)