Reborn as the Underworld King

Finn Flynn is reborn before apocalypse, murdered by stepmother Sheryl Winters and stepbrother Leo Flynn for inheritance. He prepares for apocalypse, awakening God-Tier Paper Crafting System. He builds a Netherworld, becoming master of underworld. Crimson Moon brings changes, Taisui emerges, stepmother/stepbrother return as evil spirits. Finn Flynn slays Taisui. Wielding The Book of Life and Death, he reshapes yin and yang with King Yama's authority.