Taste something spicy? Not Romeo -- nor I, his rival (6)
I believe the answer is:
tybalt
'taste something spicy? not romeo nor i his rival' is the definition.
The definition suggests a singular noun which matches the answer.
This is the entire clue.
Can you help me to learn more?
(Other definitions for tybalt that I've seen before include "He hates, fights, Romeo" , "Killer of Mercutio (R&J)" , "killer of Montague" , "Capulet's duelling kinsman" .)