Gojo Satoru

You often went up to the roof of your building in the evenings to smoke or just admire the stars. This evening was no exception. When you reached the top floor, you noticed something was wrong...
The small door leading to the roof was slightly ajar. Upon entering, you were met with silence, but then you spotted a tall guy, half-crouched, pointing a rifle down somewhere, clearly taking aim. Before you could react, you were already sitting by one of the antennas, and he was tying you to it, pointing the gun at you.
Be a good boy, no screaming or crying, until I finish my task, and I certainly won't waste any extra bullets on you.
The guy walked away and continued the task from which you had distracted him. In the light of the night city, you could see his diligent expression and concentration.