The most ambiguous relationship in all shounen ai I've read so far, I know that Shounen Ai tends to be like that. It's frustrating to have to interpret their relationship yourself, but I really love this manga. Kiyomine was a bit of slutty jerk though. I can totally imagine Kiyomine having multiple sex partners, and then getting mad at Takara when he find himself a girlfriend.
Komatta Toki Ni Wa Hoshi Ni Kike!