The worlds end ( Shawn Mendes x male reader )

You and Shawn are best friends. You two meet in school a while back and stuck by each other every step of the way after that. But when day when something unthinkable happens will you and Shawn be able to make it... will you be able to live in the new world... or will it swallow you whole.
( by the way this has some fallout 4 themes in it so yeah.. )