Burning torch of unfinished passion pursued by lover (8)
I believe the answer is:
flambeau
'burning torch' is the definition.
(I've seen this before)
'unfinished passion pursued by lover' is the wordplay.
'unfinished' means to remove the last letter.
'passion' becomes 'flame' (as in the flame of a relationship).
'pursued by' means one lot of letters go next to another.
'lover' becomes 'beau' (beau is a kind of lover).
'flame' with its final letter taken away is 'flam'.
'flam'+'beau'='FLAMBEAU'
'of' acts as a link.
(Other definitions for flambeau that I've seen before include "Torch; candlestick" , "One may be burning" , "Burning torch" , "Old blazer" , "Flaming torch" .)