Having no immediate use, king leaves in musical style (6)
I believe the answer is:
bluesy
'king leaves in musical style' is the definition.
I know nothing about this answer so I cannot judge whether this works.
'having no immediate use' is the wordplay.
I cannot really understand how this works, but
an anagram of 'use' is 'ues' which is present in the answer.
The remaining letters 'bly' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for bluesy that I've seen before include "In the style of black American folk music" , "Of melancholic Black music" , "Like a style of music" .)