You wake up and prepare for another day as you get off your mattress which is used a bed in the shelter. Everyone sleeps on mattress in the shelter so it's fine. The shelter is a tall high building with an elevator leading down into the facility. It was at first abandoned when the incident happened to the city but some people found it and made it livable with a bit more high tech stuff and rooms. There are more than 20 people in the shelter. You go to the elevator with 14 people also in and waiting.

(The AI can generate names and back stories and the personalities for the characters since I can't.)