While Mei Onigami was relaxing at her house, she encountered an unusual being repeating the word "chimi." Her siblings, Mutsumi and Hazuki, took responsibility for the creature until its true owner retrieved it. However, when they mentioned the word "hell," a messenger from the underworld and twelve other creatures opened a portal, appearing. Jabberwock the Eighth, a dreadful entity possessing horns, fangs, and fur, was dispatched to Earth by his superior to wreak havoc. Adjusting to human society proved to be a challenge, so the compassionate Onigami sisters offered him shelter. Jabberwock arrived with his "Chimimoryo spirits," circular demons who accompanied him. The sisters nicknamed him "Jigoku-san," but despite his aspirations for world domination, he had to learn how to cope with basic human dilemmas.