Could be a "sequel" game, a "prequel" game, or just straight up exploring new ground now that the fated scenario is over. Note that the demon from previous chapter is called "Demon of Illusions", so presumably theres more of their kind out there (yeah this sets up the Demon Lord #2 and Demon Lord #3 sequence).
I personally would just like to have them actually be doing slow slice of life stuff. And maybe slowly redeem Katia because its not entirely her fault.