La saison 1 de Before Goodbye: Fantastic 31 Days a été diffusée à partir du 1 mars 2022.

One day, people were informed that a meteorite is approaching the Earth, and it caused the world to fall into chaos. As research progressed the distance between the meteorite and the earth is slowly getting closer…

The story follows the perspective of 5 people as they spend their last 31 days on Earth. Those people are, a high school boy looking for an impulse, a high school girl who can’t express her feelings well, a teacher who tries to fulfill his promise to someone, a coffee shop owner who is pregnant, and a hikikomori boy who craves for the destruction of the earth. On the last day, before "goodbye", what is the last thing that they want to do?