A titled person will matter, of course (5)
I believe the answer is:
count
'a titled person' is the definition.
'will matter of course' is the wordplay.
I cannot really understand how this works, but
'matter' could be 'co' (Co is an example) and 'co' is present in the answer.
'course' could be 'n' and 'n' is present in the answer.
The remaining letters 'ut' 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 count that I've seen before include "Matter to consider" , "Dracula, say" , "Include; nobleman" , "Determine number of; foreign nobleman" , "Nobleman - enumerate" .)