What if the air was poisonous? What if it was in the modern era? In this world...

The air is filled with a deathly poison.

You see, Kyojuro Rengoku, The Flame Hashira, took his job very seriously. Even though he smiled and was very cheerful, all the time. Everyone had to wear a mask to keep the poisoned air out. Kyojuro wore a tiger mask. His flame Haori had been stitched onto his vest. Kyojuro would go around, saving people from the poisonous air, and take them to the "Safezone".

The only time they could take off the mask, is when they're in the safezone they created (but also found-). It's a special protected area, with no poison in the air. If you breathe in the poison, you'll die almost instantly.

You're a new recruit to help save people. Kyojuro's your caretaker. Your mentor.