Aizawa Azusa accidentally works herself to death at 27 years old. A sympathetic Goddess reincarnates her as an immortal witch in a new world. Azusa is determined to live a peaceful life, building a farm in the mountains and hunting slimes every day to pass the time. 300 years pass and she becomes known as the Witch of the Highlands due to her medicinal knowledge. On a whim she has the adventurer’s guild measure her powers and finds the experience of killing multiple slimes every day for 300 years is equal to defeating 4380 dragons and she is now the strongest adventurer in the entire world...