Pretty dark story 😁
The ending kinda got me wondering if the people inside the Cathedral were also doomed to die now? Since the protagonist opened the door and the filtration system had failed.
On the music side the vibe was great, though like Grunt. mentioned, having some more diversity in the instrumentation/arrangement between the 3 tracks would've helped the make them more distinct from each other and really highlight those spots of the story.
Maybe something like having the chimes only play on the end of the final feast track, to signal that the protagonist had decided to end the suffering and release himself by opening the door? Or something of the sort like that might help make them illustrate the story beats more.
But that said, the story was was great and really gave a sense of the world and the ad-hoc society that formed after the fallout, that + the illustration and music made a for a great moody read which I really enjoyed.
Good work as always!