I'm going to sit on my roommates couch naked
Why do you think you need to do that?
I just want to watch tv naked
While I don't think there's anything wrong with you sitting around naked in your own house or room, I do not think that it is good for you to be naked on someone else's property like your roommate's couch. Your roommate may have worked very hard to get that couch, and may not want you to get it dirty or they wouldn't feel that it's hygienic for you to sit around it naked. How about you buy your own couch to sit around naked on?
Nobody cares about hygiene and I bet my roommate wants to see me naked.
You can't just expose yourself to your roommate. You don't know if your roommate even wants to see you naked so just wear clothes.