Novelist: one’s leaving chorus to the end (7)
I believe the answer is:
lessing
'novelist' is the definition.
(Doris Lessing)
'chorus to the end' is the wordplay.
'chorus' becomes 'sing' (to chorus is to sing in chorus).
'to' is a charade indicator (letters next to each other) (I've seen this in other clues).
'the end' becomes 'les' (I am not sure about this - if you are sure you should believe this answer much more).
'sing' after 'les' is 'LESSING'.
'one's leaving' acts as a link.
This may not be correct. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for lessing that I've seen before include "Writer" , "Doris - - , novelist" , "source of drama" , "Doris -, British author" .)