If you do NOT see your favorite pairing there, DO NOT VOTE yet. I will edit the poll so that you can vote for the one that you want. And on that note, I will only add a certain kind of pairing if someone asks for it, though I know that there are certain ones popular...
Yai - The thing I see about Yai is first, her age difference is a major problem. Second, it seems that she has a crush on him, but he sees her as a younger sister. I have read however a few good fanfics for this pairing, but not very many.
Annetta - I can see the pairing, but... I have to admit I got set away from this with two Enzan/Annetta enthusiasts over analyzied things, like Enzan yelling her name, the white flowers, that he ate her food... that kind of thing. And Annetta is slightly annoying personality wise.
Meiru - She's paired with Lan... end of story. Though I can see it. I read a really good fanfic for this pairing that put Enzan and her together because she couldn't wait around with Lan. It was believable.
Shuuko - It's cute... but no interest. Have yet to read a fanfic for it.
Jasmine - Same as above...
Iris - Same as above...
OC - A well developed OC is what I really like, someone who is a good match personality wise and isn't unbelievable, can take care of themselves, but isn't completly indipendant. That is a good OC.
Now for the pairings I didn't put.
Netto - I can see it, but... I don't read it... and I would think he would drive Enzan nuts from his hyper activity.
Laika - Can see it too, but he would drive Enzan nuts with his OCness... and not the OC original character kind.
Yaito - I agree with the problem about the age difference. Enzan would have to be quite the pedophile.
Anetta - The pairing I prefer. Anetta definitely likes Enzan and Enzan showed he cared about her too, going out with her all and feeling guilty about (sort of) killing Silk.EXE.
Meiru - Well, she marries Netto.
Shuuko - I actually like to see Shuuko together with Higure.
Jasmine - Haven't seen the anime up to this point yet and haven't played the games.
Iris - Same as above.
OC - I'm not very much into fanfiction.
Netto - I'm not a supporter of shounen-ai pairings unless they're pretty much official. It seems some fujoshi like to pair any anime guy with any anime guy, as if they were all gay.
Yaito - The pedifile thing ALWAYS makes me shudder.
Annetta - I can see it, seriously... but those two girls rather set me off of that pairing.
Shuuko - Was just thinking it was interesting... and wondering if anyone prefered that pairing. I actually like her with Tohru.
Jasmine & Iris - I think that is the same reason.
OC - No big deal... but some people do prefer OC pairings to canon characters... like myself. Not everyone digs the fanfic thing. Case closed on that one.
Shounen-ai - For me, it really doesn't have to be official... and I think your right about some people just wanting to pair of two boy characters... or two girls for that matter... actually happens in a lot of fandoms.
Most likely to be paired would be Anetta but I'm not totally cheering up for her. Yaito's too young though I would prefer her tsundere-ness for his quiet personality. Meiru would be fine as well but she's with Netto/Lan. Iris.. I guess I like her a lot so I'm kinda bias.