We are releasing the original soundtrack DLC of Iris.Fall today. It contains 10 songs. You can get it for free if you have already purchased the game.
https://store.steampowered.com/app/1025040/IrisFall_Original_Soundtrack/
Iris.Fall is 50% off from Feb 20th to Mar 6th ( PST ) . Go grab it while it's on sale and get the OST for free!