Dragon and Tiger Taoist

The heaven and earth have spiritual power, and all things feed on the spiritual power and grow.
All kinds of people can become monsters, extend their lifespan, and gain supernatural powers, except for humans.
The human body is deficient and has no ability to accommodate spiritual machinery, but the human soul is pure and spiritual, and is born with a shortcut. Therefore, those with great wisdom find another way to cultivate immortality through demons and harvest the fruit of immortality.