For some reason, darkwave. I never listen to it in any other context.
Then there are specific albums that I love but am so familiar with that it just plays in the background if I'm doing something else, like comfort listens. So that's Refused - The Shape of Punk to Come; Gang of Four - Entertainment + Solid Gold; Bloodborne + Old Hunters OST; No New York; James Chance and the Contortions; Shin Joong Hyun