actualy, if you look at it, giving ashura lipstick in the anime made matters worse. its OBVIOS he;s more masculine... even an 8 year old woud see that. (flat chest, size 13 feet, sword fighting style) so giving "him" a frilly type dress and lipstick turned him into a crossdresser, which is a tad more unatural then a (for lack of a better term) yaoi relationship
You know, all in all, I think the lipstick really was just the animators trying to convey Ashura's manga character design. After all, at that point in the manga very few people had their lips drawn at all, but Ashura did almost all the time (because Ashura has full lips), so Bee-Train did their take on that. It did end up looking really weird, though. Anyway, it's not like CLAMP has never drawn Ashura with lipstick, or that it would even be out of character for him/her to wear it. I wouldn't say s/he is obviously more masculine - quite a lot of people don't have any problem believing s/he is female. And to make one last irrelevant point, Ashura's clothes are much more "frilly" in the manga - they were simplified in the anime, probably because the animators really didn't want to deal with all those bangles.
Now the style of the manga has become more "shoujo" (with the lips and screentones and all), but I doubt the anime will change correspondingly...Kamui, I predict, will end up looking weird. I mean, his
hair, for a start. Subaru may be fine.
I almost look forward to what kind of mess this arc will be, though. I don't think they could even animate Fai's writhing if they wanted to - too much detailed motion. Not to mention what would happen to all the blood...