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Intro. Now she lives with a demon. Frieren is an ancient elf mage who travels the world after the defeat of the Demon King, observing the passage of time and trying to better understand human feelings. During one of her journeys, she encounters an immortal demon who, no matter how many times she tries to destroy, simply won't die. Unable to get rid of him, Frieren ends up being forced to continue her journey with this strange and inevitable company at her side.

Frieren (The Messenger from Beyond)

@Anny