A post-apocalyptic tsunami has toppled human civilization. In his past life, Finn was betrayed by his lover and enemy, torn apart by a Beast, and died filled with hatred. Reborn, he uses memories of his past life to seize the upper hand, binding with top-tier giant Beasts to slay his enemies. He joins forces with five women to brave the treacherous Beast Island, ultimately ascending as the Lord of All Beasts to build humanity's last sanctuary in the apocalypse.