At this point this isn't subtext any more, its just text.
I'm not so sure. I think it's pretty obvious they both love each other a lot, but Sakrurako is the only one to show she is attracted to her roommate. Although she doesn't really act on it, she very frequently thinks about how lovely Kasumi is. It's kind of hard to tell with Kasumi since she is so sedentary and chill if she actually has those sorts of feelings or not, but she definitely enjoys being cozy with Sakrurako even if its not sexual in nature.
Although it fits with her personality, Kasumi really is quite unusual in that she is a high school age girl that does not seem to have any sort of sex drive at all. I don't think we have seen her even so much as thinking that another person is attractive let alone acting on it.