Once life on earth will cease to exist, the character will move on to seek another asylum. It will be a different planet. Maybe that’s where it will learn something new. It certainly will not be as green and full of life, because it once has had one like that.
The planet will create new lights, dark spaces, a horisont where one can see himself differently. Spend time to think about how to survive and not to destroy it again.
The characters are entities that will adopt to the new environment. Their outer shapes will reflect the imagined planet’s surfaces.