Pearson's unusual character (7)
I believe the answer is:
persona
'character' is the definition.
(I know that character can be written as persona)
'pearson's unusual' is the wordplay.
'unusual' is an anagram indicator.
'pearson' is an anagram of 'PERSONA'.
(Other definitions for persona that I've seen before include "No pears (anag.)" , "Public image" , "character on the stage?" , "One who is diplomatically acceptable" , "Assumed identity" .)