fictional character vs fictitious character

fictional character and fictitious character both are nouns.

Word	Noun	Adjective	Verb	Adverb
fictional character	Yes	No	No	No
fictitious character	Yes	No	No	No

As nouns, fictional character and fictitious character are synonyms defined as:

fictional character and fictitious character: an imaginary person represented in a work of fiction (play or film or story)

Other synonyms of fictional character include character.

fictional character (noun)	fictitious character (noun)
an imaginary person represented in a work of fiction (play or film or story)	an imaginary person represented in a work of fiction (play or film or story)