Iruma Suzuki is a 14-year-old boy who has spent his entire life working dangerous jobs to support his lazy and irresponsible parents. His life takes a literal hellish turn when his parents sell his soul to a powerful demon named Sullivan. However, instead of being eaten, Iruma is shocked to find that Sullivan simply wants to adopt him as his beloved grandson and spoil him rotten.

Enrolled in Babyls Academy for Demons, Iruma must navigate life in the Netherworld while hiding the fact that he is a human—if his classmates find out, he’ll become their next meal! Despite his desperate desire to blend in, Iruma’s supernatural dodging skills (developed from years of surviving his parents' antics) and Sullivan’s eccentric interference constantly thrust him into the spotlight. From accidentally summoning a teacher as his familiar to befriending the school’s outcasts, Iruma begins to realize that the demon world might actually be a much kinder place for him than the human one.