Five years ago, scientists discovered that the sun is degrading at an accelerated pace, destined to devour Earth in an unknown amount of time. However, no one was willing to resign themselves to such a fate...

Soon, executives formed the United Government, with a single effort in mind: continue our legacy.
Their answer was to pool all of mankind’s remaining resources to manufacture gigantic space vessels called Arks. These marvels of technology would soon breach our skies to reach a new frontier.

We succeeded. The Arks broke through orbit to carry on humanity's spirit to survive. But none of that had anything to do with me… I was unqualified to board one.

My plan is simply to carry on as normal, to continue taking exams in my old classroom. I wish to at least retain my pride when I finally leave this life.

However, she had other plans. She wanted me to ask her want, just so we could face our dooms together.

[from Steam]