Supporting character

Character in a narrative that is not focused on by the primary storyline

A supporting character, also known as a secondary character or side character, is a character in a narrative that is not the focus of the primary storyline, but is important to the plot/protagonist, and appears or is mentioned in the story enough to be more than just a minor character or a cameo appearance. Supporting characters differ from minor characters because they have complex backstory of their own, desires, and emotions. While this is usually in relation to the main character, rather than entirely independently, developed supporting characters add layers and dimension to the story and the protagonist.

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