Fantasy: After Traveling Through Time and Becoming a Demon King, I Just Want to Live a Good Life

Su Yu, a college student, traveled to the world of swords and magic. He originally thought he would be happy all the time, but he was shocked the moment he saw the system profession. "Holy crap! Why is my profession the Demon King?" "You haven't even been promoted to a level yet!" After others traveled through time and became demon kings, they always thought about how to dig holes for the brave, but Su Yu, a college student, just wanted to practice leveling up and retire, and marry the eighteen-room succubus... A hundred years later, the aging hero looked out the window with regret. Although the world was stable, he could not find the Demon King throughout his life. The demon king Su Yu, who was hiding in the human city-state, stopped teasing the blacksmith's daughter and sneezed inexplicably. "Which sister misses me so much?"