Sir the Hero of the Apocalypse

Overnight, a new type of virus spread throughout the United States, but those who were lucky enough to survive had to face various difficulties in order to survive. People infected by the virus have become the living dead. They have no breathing and no emotions. They just kill blindly. They mutate in the killing and become more agile and powerful. In order to fight against these living dead, the living people formed a team under the leadership of the leader. This team is composed of twelve humans with outstanding abilities from all over the United States. People call them the Twelve Heroes Sir. Two of the Twelve Heroes, Li Haoyu and Cheng Lulu, gradually fell in love after experiencing life and death battles. Until that day, after Li Haoyu completed a special mission, he knew the truth about why he became like this. And this truth had a lot to do with his lover Cheng Lulu...