My Body Is Immune to Zombie Viruses

[No system, no harem, no powers] When he woke up, there was an outbreak of zombies in the city, but he was walking among the zombies unharmed, buying it for absolutely zero dollars. "So they will all die, right? The so-called miracle medicine just dies slower." "You told me so much just to make me feel less guilty, right?" He waved his hand, and thousands of zombies followed the order and attacked.