Seo Min-woo, an ordinary man, inherits a suspicious kindergarten as his late mother's legacy. This is a kindergarten attended by various mythical beast children, including a tiger, rabbit, cat, snake, turtle, and sheep. Guided by the system, Min-woo becomes the new principal and learns the secrets of a world on the brink of war with demons. He grows as he climbs a dangerous tower with the mythical beast children.