I Will Always Protect You

A hundred years ago, Long Xiaotian's momentary carelessness led to the deaths of his young lord and the young lord's wife at the hands of their enemies. To atone for his failure, he sacrificed his chance to be reborn, ensuring that their souls would endure for a hundred years. He kept his memories and spent that century protecting his young lord's reincarnation and bringing the reincarnated couple together so they could marry.