Shibuya Academy is a campus full of troublemakers, where constant brawls and disorder reign supreme. Yet one principle is universally respected—never challenge freshman Tatsumi Oga, the toughest fighter on campus.
One afternoon, Oga sits beside a riverbank when he spots a man drifting downstream. After rescuing him, the man splits open to expose a newborn, which immediately climbs onto Oga"s back and bonds with him. Unaware of it, the infant is christened Kaiser de Emperana Beelzebub IV, or simply "Baby Beel"—the offspring of the Demon King.
Just as discovering the future ruler of Hell seems enough, Oga also meets Hildegard, Beel"s demonic housekeeper. Together they set out to raise Baby Beel—though surrounded by juvenile offenders and supernatural forces, the duo may face far greater trials than anticipated. Their journey will test their resolve, push the boundaries of loyalty, and force them to confront the darkness that lurks within hearts and demonic realms.