In 2098, the virus broke out and the end came. There are infected everywhere, don't get bitten by them, otherwise you will be honored to join them. What is the end? The last day! Only by obeying the laws of doomsday can you be reborn! Doomsday rules: 1. Don't be bitten by zombies. 2. Don't seek death casually. 3. Don't be a saint. 4. Don't trust others casually. A mysterious man who is extremely cold both in appearance and in his heart, a high school assassin who is as gentle as water and always smiles with squinted eyes. Good friends, let's form a team to fight monsters together.