I Will Always Protect You

A hundred years ago, Long Xiaotian let his young master and the young master's wife die at the hands of their enemies through a moment of carelessness. To make amends, he sacrificed his own chance to be reborn, preserving their souls for a hundred years. He himself retained his memories and spent a century protecting the young master's reincarnated self and bringing about the reincarnation of the young master's wife, so the two could reunite as husband and wife.