Flirt with one in pub with lighter? (9)
I believe the answer is:
philander
'flirt' is the definition.
(I know that flirt can be written as philander)
'one in pub with lighter?' is the wordplay.
'one' becomes 'i' (Roman numeral).
'in' indicates putting letters inside.
'pub' becomes 'ph' (abbreviation).
'with' is a charade indicator (letters next to each other).
'lighter?' becomes 'lander' (someone alighting or landing).
'ph'+'lander'='phlander'
'i' inserted within 'phlander' is 'PHILANDER'.
'with' acts as a link.
(Other definitions for philander that I've seen before include "Have affairs" , "Have an affair" , "Flirt, chase women" , "Play the field" , "Womanize" .)