"Azhi, you can feel guilty, or you can carry this guilt to save more people, but don't let guilt become your whole life." Jiang Zhi lived in guilt all his life. He "atoneed" for his guilt throughout his life, and finally died in the hands of his best friend Mo Xuzhen with guilt.
After Mo Xuzhen killed his best friend with his own hands, he had nothing from then on. The winter that year was so bitter that even the air was filled with bitterness. After a bitter winter, every winter in Mo Xuzhen's life was bitter.