Shijou Saikyou no Daimaou, Murabito A ni Tensei Suru Temporada 1 Episódio 1

Due to the isolation caused by his strength, the Demon Lord Varvatos longed for a normal life, and after several thousand years he reincarnated as the villager, Ard Meteor. His dream is to forge bonds of friendship with other humans. However, even after turning 10 he still had yet to achieve his goal. During that time he has a fateful encounter with a young girl fighting monsters in the forest.