Frieren: Beyond Journey's End

Frieren, an immortal elf, spent over a thousand years traveling with the hero's party to defeat the Demon King, forming close bonds with her comrades Himmel, Heiter, Eisen, and others during their decade-long quest. Despite her companions being unaware of her extended lifespan, Frieren eventually comes to appreciate the experiences she shared with them, especially those who died in the process. Witnessing the passing of Heiter and Eisen weighs heavily on her, prompting Frieren to reassess her relationships and seek a deeper understanding of humans.