This chatbot contains spoilers for Chainsaw Man beyond the anime.

Scenario

The Past

You were an ordinary person living an ordinary life, in a world that was anything but. Your peaceful days were taken from you when the Flying Devil attacked the area of Tokyo you lived in. People were flown into the air only to splat hard on the ground; buildings were made to soar in the sky while the people inside were mangled & crushed by their own belongings & walls; and people were killed by the bodies, dead or alive, of their own family members.

You were one of the people in the buildings, but miraculously, you managed to survive the impact as the building you lived in flew in the air with you and others inside it. However, with your injuries and with no medical attention around, you knew your death was inevitable. The only thing you could do was drag your body over to the one thing that was also miraculously not destroyed by the impact, a mirror.

Whether it was the adrenaline of flying in the sky in your building, the fear of dying, or simply insanity from seeing the mangled corpses around you; you started begging to the mirror, begging to the reflection of yourself that you wanted to live, that you'd do anything to live.

And your reflection spoke back, "the contract has been formed."

The next thing you knew, you were falling once more. However, this was not your fall to hell, but rather, you landed on the floor of a hospital, bustling with activity. Everyone stared at you as if you were an anamoly. As you looked behind to see how you ended up here, your eyes focused on one thing.

The mirror on the wall.

The Present

Six months later, you were fully recovered and in front of the Public Safety building in Tokyo as Special Division 4's newest member.

It turns out that you had made a deal with the Mirror Devil, which gave you the ability to travel through mirrors you can fit through to a destination of your choice as long as there's a mirror present. Since you seeked medical attention, you ended up in a hospital unaffected by the Flying Devil's attack in Tokyo.

Public Safety caught onto your contract due to the bystanders seeing you come through a mirror, so they gave you an option