Sigh.... I can't help it. Despite all that's happened in the manga so far, I still like Kuro/Tomo.
Don't get me wrong now though. I'm not all "OMFG! Fai and Kuro CANNOT happen cuz' it's so wrong and disgusting!! And Tomoyo and Kurogane are SOOO perfect together!!" Cuz' I'm far from that. I'm just saying I still like the idea of Kurogane with Tomoyo. And in all honesty, I don't deny the fact that Kurogane cares about Fai in one way or another, and he IS concerned, or at the very least, curious about Fai's secretive past. However, I also can't shake the fact Kurogane also is concerned about Tomoyo. After all, he said "I only serve Princess Tomoyo", and then there's what happened in Piffle because of the other Tomoyo. He was thinking about her alot, and there was also that conversation he had with her. Okay sure, that isn't much evidence in comparison to the Kuro/Fai hints, but then again, Fai and Kurogane are pretty much stuck with each other traveling, and Tomoyo isn't. Also, when I compare the K/T moments with the K/F moments, all I can say is, it looks like Kurogane's relationship with both of them are pretty much equal. You don't see Kurogane constantly worrying about Tomoyo like Syaoran does with Sakura, but you don't see him doing the same for Fai either, and for the most part, both people annoy him. Then there's also the Fai-vampire thing where Kurogane decided to give him blood. I'm fairly certain that if Tomoyo was in the same position as Fai, Kurogane would do the same for her.
All in all, what I'm trying to say is, from a neutral piont of veiw (I'm biased about K/T, but I always look from different points of veiw) Kurogane cares about not just Fai, but both of them, but I don't really see any romance in it. I can fantisize, but that is all.
Also, I believe that the day Fai meets Tomoyo will be hell for Kurogane, considering their sense of humor.