The Sun Rises, the Moon Sets, and All Returns to Dust

Both pure and devoted x both powerful x no female lead x a champion of pure love

Three hundred years ago, a young master and a beggar were fated to meet, but not to be together.

Three hundred years later, a demon king and the young master of an immortal sect are fated not to meet, and not to be together.

The demon king defies heaven to pursue his wife by force. Disguised as a young cultivator, the Demon Lord follows his wife and helps her beat the demons into the ground.

When the great battle begins, the demon clan's leader runs away, then the second-in-command runs away, and then the third-in-command flees with the entire demon army!

The demon king spends the whole journey acting weak and helpless, putting on a brave face when injured and throwing himself into his wife's arms...

But in the end, the demon king's secret identity is exposed...