There Is No System, I Made It Myself

A young man from Earth is reborn in another world after his death. System, grandpa, grandma, none of these... He has none! At first he thought that special conditions were needed to activate his golden finger, but a thousand years later he was sure... I just simply don't have a golden finger! ! After giving up, he concentrated on practicing. Over the past many years, the young man created a system, but... This system seems useless! ! !