Confer Gods and Become a Sage: Teaching Little Demons How to Be Human

A transmigrator caused the Investiture of the Gods to fail, leaving the human world as territory of the demon race. The protagonist transmigrates into this world and starts by taming the demons so they can live in harmony with humans. He sets the Investiture of the Gods in motion again, seals away the demon race, and sets the entire world right, restoring it to its proper course.