In a realm where humans subjugate other species, the renowned archmage Rifenhardt is vilified as the Demon King for aiding the oppressed races. When a group of valiant heroes sets out to vanquish the feared Demon King, Rifenhardt inflicts severe wounds upon the party but ultimately faces his demise at the hands of Tesslon, the Martial Fist King. Desperate, he invokes the forbidden 'Time and Space Regression Spell' and is propelled back in time. However, a startling revelation awaits him in this altered past: he reawakens as the very hero he once sought to defeat, now revered as the strongest warrior on the continent. Thus commences Rifenhardt's extraordinary journey, navigating the realms of magic and physical prowess to reshape the fate of the world.