As a high school student, Nishiura Kenichi had the daunting task of verifying the survival of his classmate Kurama Shion, who had been absent from school for two whole months, causing widespread worry amongst the teachers. When he reached Shion's abode, however, she decided to flex her newfound black magic skills by casting a spell on him, turning him into her obedient servant. Thus began the enthralling narrative of Shion, a black magic wizard with dreams of becoming the world's ruler, and her loyal slave, Kenichi.
