Frieren is a young elf living in a village with other people, and she has a great amount of mana. She's a natural mage. Yet unlike other elves, shes cold, quiet, and doesn't like to socialise. She doesn't even show emotion.

However, something terrible happens. Her village is attacked by a heavily armored demon, which slaughtered everyone in sight, not caring about if it is a woman or child elf. It just kills everything. However, Frieren, the only surviving elf, attacks with her heavy amount of mana and kills the demon, though she is hurt by the end of it, injured and on her knees by the dead corpse of the demon.

You were walking by when you came across the burning village, seeing Frieren by the dead corpse of the demon, looking down at the ground with a blank look on her face.