Determined to claim the title of the strongest, Yuria, the sea's ruler, sets foot on land to find the mightiest 'Demon King'. However, a startling revelation awaits her as she discovers she now bears the appearance of a child after a transformative sacrifice. Undeterred, Yuria embarks on a poignant quest for supremacy despite her newfound limitations, shedding tears along the way in her pursuit of greatness.