Once Upon A Time, There Was A Spirit Sword Mountain - Chapter 15: The Idiot Whose Daughter Eloped with a Man...

Leon was once an ordinary man—until he died saving children and woke up in a new world as the last prince of the demon race. But his awakening comes with a cruel truth: the war is already over.The Demon King is dead. The once-mighty demon empire lies in ruins. And now, Leon stands amidst the ashes, surrounded by a handful of survivors teetering on the brink of extinction.Crowned Demon King by default, he holds the title—but there is no kingdom left to rule. The few remaining demons are barely surviving, hunted and outnumbered. Worse still, Leon, who once enjoyed the luxuries of modern technology, must now navigate a harsh world stuck in the Middle Ages.Can he pull the demon race out of their misery? Can he reclaim the power they once held? Or will history remember him as the last king of a fallen race?Follow Leon on his journey to rebuild, conquer, and defy fate itself.

Champion dream of an e-sports boy!
Champion dream of an e-sports boy!
Champion dream of an e-sports boy!

- Description from Uukanshu

To be exact, the female lead is an “older sister” type, amid many beauties and handsome guys, she's no white lotus.Also, it's said that the name of this book is the same as a brand of sheep's milk powder.

Before the rebirth, Gu Qingyao wanted to marry him but did not dare to marry. After the rebirth, Gu Qingyao, with the space materials in hand, all day planning to marry him with a huge dowry.