A 30-year-old Japanese salaryman, Minoru Kido, dies in a traffic accident. As he fades from existence, his only regret is having left no mark on the world. His wish for a second chance is granted when he reincarnates as Liese Klein, an elf in a fantastical realm where his new race can live for up to a thousand years. Retaining all his memories from his previous life, Liese vows this time will be different: he will master his talents and carve his name into history.

Liese spends his early years in his elven village, diligently studying magic. His efforts yield astonishing results. By age twenty, he has full command of all healing magic inherent to elves. By thirty, he has mastered every attribute of magic. Most impressively, by the time he reaches one hundred years old, he has deciphered all known ancient magical formulas, reaching the absolute peak of magical power possible in that world. A century after his rebirth, having fulfilled a challenge from the village chief to realize his potential, Liese finds himself with an unprecedented amount of time left on his hands: nine hundred years.

Refusing to let his long lifespan lead to idleness, Liese leaves the safety of the elven forest to begin his true journey. He is driven by a simple yet profound desire to live a fulfilling life and ensure that his existence is remembered. As he travels across the world, his overwhelming power attracts attention. He encounters a nameless human girl whom he names Minori, and later takes on an adventurer named Jin as his apprentice. The narrative follows Liese across the centuries as his actions ripple through history. He is rumored to have trained a fledgling adventurer who would later be hailed as a hero, inadvertently founded a nation in his name, and was eventually worshipped as the founder of magic. The story chronicles the journey of a reincarnated elf who, armed with nine centuries of life and unmatched magical prowess, seeks to become a living legend by leaving an indelible mark on the world.