Here are some pairings I've seen Kuwabara pairings in. I'm going to use my own opinions on the matter, and some facts. So here we go. I really don't like this pairing. Any yaoi pairings with Kuwabara, I totally dislike. I don't know, I just can't see this happening. They fight a lot, but they're best friends. Best friends usually get up with each other, but I wouldn't like to see it in this case.

With facts...Togashi-sama didn't want anyone in the show to be gay, except for Itsuki and Sensui. He thought the Kurama x Hiei idea was okay, but didn't use that. (Of course, I shouldn't be saying that in the Kuwabara section!) But yeah. It wouldn't happen, and it hasn't happened.
No. <3 >;x There is no pairing I hate more than the Kuwabara x Hiei pairing. They despise each other. They rip at each others throats almost every waking moment of the day. Whenever Kuwabara breathes Hiei says it's wrong! So of course they couldn't say, "Hey baby, I'm sorry for saying that! Let's go to my room!", hit the sack, and engage in hot ass sex! How could you even see this? I mean, whatever floats you boat is fine, but I really hate this pairing.
._____________.;;; Um, well... Kurama's a nice guy, and he's one of Kuwabara's best friends. Like I said before, best friends usually get with each other. But in this case, the most they'd ever do is give each other a friendly hug and get on with their lives. I mean, for God's sakes! Could you see them actually having sex and enjoy it? I know I can't! But again, that's just me.
Ah, a straight pairing! I love this pairing so much, but it can't happen because Hiei is over protective of his sister, and doesn't like it when she's around Kuwabara. So yeah. Might not happen, but then again, it might. Yukina doesn't understand what Kuwabara does when he displays all this affection for her. She just giggles and rubs it off her shoulders. She was born into a race of ice maidens who have never seen the face of man before, so how would she know what it's like to be with one? Now that she's in the human world, she might be able to see that males aren't like what the ice maidens portray them to be. So yeah. It could happen.

If you see a pairing not listed here, drop me a line and tell me about it! Like who the person Kuwabara is paired with is, and your opinion on it. I'll post it up here along with mine. <3