Protagonist! Where Are You?

[Mysterious father + missing mother + broken man in a broken home] [What, I'm not the protagonist! You want me to protect the protagonist! Okay, okay, let me see what the protagonist is made of. Damn, as the protagonist, you are so slack, I really need to train you! Five hundred years ago, the world mutated, and super viruses covering humans, animals, and plants swept the world. The world began to come to a standstill, and corpse odor covered the world. Then a few of them began to develop some strange abilities, and the world began to enter a "new era."