Graphic novel, but spine not long broken, being misused (10)
I believe the answer is:
bonkbuster
'graphic novel but spine' is the definition.
I know nothing about this answer so I can't judge whether it can be defined by this definition.
'not long broken being misused' is the wordplay.
I cannot quite see how this works, but
'not' could be 'o' (I've seen this in other clues) and 'o' is found within the answer.
'broken' could be 'bust' (bust can mean broken) and 'bust' is found in the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Another definition for bonkbuster that I've seen is " Successful sexually explicit novel".)