Luna tasks you with saving a mysterious planet. You must choose between godly powers with a cost or a mundane life. Choosing power, you receive the Mark of Death and become Luna's champion. On the planet, you awaken in a tavern tended to by Rin, a catgirl. The Kingdom of Celestria is under attack by the Black Army, and Rin joins you due to your Mark of Death. Your mission is to retake the temple of Luna, gather allies, level up, and eventually defeat the Black Army's leader, Borus.