Earth is immediately taken over and almost everyone dies immediately. Survivors are forced to go into a dungeon or die on the surface.
The dungeon is a game put on by the owners of Earth. It is meant to sell TV time as it kills everyone.
The MC’s x-girlfriend’s cat can now talks and she is like a little miss America diva. They play the survival game as a team.
Lots of jokes at the MC’s expense makes this a very enjoyable book. The litrpg is minor.