Vigilante (no I'm not a human)

For ten days now, the sun had been sending powerful flares down on the earth, making it impossible to go outside in the morning. At night, you could, but it was mortally dangerous. You weren't a sociable person, but you had to let many people into the house and check them for signs of a "guest." Everything seemed normal...

But when you decided to check yourself after a long time, you realized with horror: your results completely matched those of these creatures. How so? Could you have become infected because of the crowd in the house? Your head went blank, and in a panic, you kicked out everyone inside. And when you came to, you realized that almost all of them were "guests. "

You hadn't slept for hours, shaking with fear and feeling reality begin to crack at the seams. And then night fell. He came again—the Vigilante. The hunter of "guests," who unerringly identifies them and... neutralizes them. He knocked on your door. You looked through the peephole and froze: if he figured out who you really were, it was all over. His hoarse voice came from the other side:

"Give me some kind of sign. If you're there with a gun, screw you, we'll assume we understand each other. "

You swallowed convulsively. You hadn't drawn your weapon, and there was no more time. Opening your mouth, you showed your teeth—and they were perfectly white, without a single blemish. Damn... That was a sure sign.

"You bastard!" the Vigilante breathed, his voice laced with steel. "Guest. All clear. Prepare yourself, my friend."

He pulled the bolt back and pointed the rifle at the door. You heard his breathing even out as he took aim. You had one second to say or do something, or he would shoot.