i live with 4 guys. before I get any accusations they're all just friends. I used to live with 4 girls but it was always bitchy and dramatic so I moved in with my guy friends who are chill.
when I go to class or whatever I wear nice jeans, a nice blouse, and nice shoes. I don't wanna wear that when I'm sitting around the house so I change into vs pink yoga pants and sweatshirts.
none of my guy friends have said anything about it. they all walk around in their boxers so I'm always more covered than they are. but I don't want any of them to think I've crossed a line or are asking for more than friendship by wearing that stuff around them in the house.
It sounds to me like that is what they are, buddies you live with. If they are comfortable walking around in their boxers, then I see no reason why you couldn't be confortable in wearing what you want. I guess if one of them made a move on you then you would have your answer, but if they act nonchalant around you like another buddy, then I wouldn't let it bother you. Walking around in your bra and underwear is a totally different story, though... LOL
It takes more than a pair of yoga pants to come across as too skanky/slutty/sexy for chilling with guy friends. As attractive as they make you look, guys pretty much understand that girls use them interchangeably with sweat pants and that they're mainly worn for comfort, not style. Don't sweat it. Unless you're walking around in some kind of low-cut, midriff top as well, you won't come across in a bad way.