After the Abyss Rift descended, humanity entered the era of beast taming. Ordinary people can only contract spirit beasts, while office worker Ethan Wright accidentally awakens the "Eerie Evil God Dominator System", becoming the only person who can contract eerie fierce creatures. To save his seriously ill sister Mia Wright, he successively contracts powerful eerie beings including Nyx, Hecate Voss, Seraphina the White Serpent, and Skinweaver.