A complex character can be called many things. Believable and realistic are two words, but perhaps you are thinking of "round" characters as opposed to "flat" characters who are not complex.
Round
A word character means a character that has many meaning to it. Example: Goofy is silly. SILLY is the word that describes or has that meaning to a character.
Antagonist. Tormentor.
static minor character
Eponymous
Holy order
"Empathetic" is a word that best describes the character in humanism since humanism emphasizes the importance of understanding and valuing others' experiences and perspectives.
out going and helpful.
dynamic
Nova net:: Individual
The word most is an adjective. It describes a noun.
poetic