Hi! Thanks a lot, happy to hear that :)
I love HROT too, great game.
The music is from various artists, its all from audio jungle. I've put the links to the music (in game and menu) here, I dont think I would be able to put them together and sell them separatly for license reasons. But if you dig them you can purchase them yourself on audio jungle or possibly listen to them on soundcloud or something like that if they have their stuff there. Here are the links:
https://audiojungle.net/item/suspense-dark-drone/45405124
https://audiojungle.net/item/suspense-dark-background/42304902#
https://audiojungle.net/item/dark-tense-suspenseful-music/30070420