No one knows what regret is until they do.

Xuan Cheng, a former disciple of Kunlun Sect who then later becomes a demon lord, killed his senior brother for betraying their master. However, he learned the truth when his senior brother finally died. By then, it was all too late.

Not long after his senior brother died, Xuan Cheng also died. Thinking that he would go to the after life, he was surprised to be greeted by his shixiong's face first thing in the morning. After confirming that he wasn't dreaming, Xuan Cheng vowed that he's now given the chance, he would dedicate his second life for his shixiong and won't repeat the mistakes he made in his previous life.