Author's negative response is reflected in titular character (6)
I believe the answer is:
eponym
'titular character' is the definition.
The answer and definition can be both related to communication as well as being singular nouns.
Maybe they are linked in a way I don't understand?
'author's negative response is reflected' is the wordplay.
'author's' becomes 'my' (belonging to the person writing).
'negative response' becomes 'nope' (informal version of 'no').
'is reflected' shows that the letters should be reversed in order (letters reflected back).
'my'+'nope'='mynope'
'mynope' reversed gives 'EPONYM'.
'in' acts as a link.
Can you help me to learn more?
(Other definitions for eponym that I've seen before include "Word derived from person's name or placename" , "Hero" , "someone giving a name" , "handle from place?" , "eg 'Jane Eyre'" .)