Well, see, I am a little confused. He acts like he is in heat whenever Yuka is around, and he has to take medicine. That makes me think "omega". But Yuka starts getting his heat whenever Kaoru is around...and that is more like a reaction to one's fated match. So maybe Kaoru is some sort of super sensitive alpha that has to also take medication to calm down because the hormones in the school are really affecting him.
Or.....this one could be really going against the grain and they could both be omegas but somehow still each other's fated pair...and setting each other off in their heat whenever they are near.
I mean it is already off that they don't "test" them until they are in junior high (as I recall, puberty can start hitting some people before they even reach their teens...so waiting so long to test them seems a bit dangerous). It is also funny how everyone acts normal until after their test. And then suddenly they start developing the traits for their "gender" within days of the test. Whew...they got tested just in time (insert sarcasm here).
Sorry, I am enjoying this...but couldn't resist poking at one of the plotholes
there is no raw for ch4 yet though XD

Darn it I'm confused now, somebody said Kaoru is an Omega, but why in the world he is acting like that whenever he saw Yuka. He is acting like an Alpha