So I bet many of you are wondering why I have become so dedicated to Xelloss and Lina coupling that I'd actually spend this much time on it. (Well, maybe not that interested, but let's say you are.)
Honest to truth, I'm not really that obsessed anymore. It was one of those fangirl obligations to match a favorite character (Xelloss) with a girl from the series (Lina).
I still love them, though. I'm just more convinced now that it's a farfetched idea that, really, would have no chance of happening. I bet Kanzaka Hajime (the author of Slayers) never even thought of Xelloss and Lina being a possible coupling.
But this is just a coupling rant. I guess I'll have to explain why the other couples just don't do it for me (None of these characters, on his or her own, ticks me off. I just have something against a certain pairing(s)). (Scroll all the way down for Xelloss x Lina reason)

Lina and Gourry:
Well, at first I really detested this coupling. I didn't develop a liking for Gourry's character (and consequently fell in love with Zelgadiss at first sight). I still don't have a fond liking of this couple, but I have nothing against it anymore. It's the way the author intended it to be, no matter how much we all may protest against it. And, honestly, they're not all that bad. It was only natural that Lina liked him, considering he's very nice and not bad-looking. Think as a human and you might understand why they ended up together.

Amelia and Zelgadiss:
My anti-AZ spawned from every site online saying "Amelia is so annoying!". I, too, thought she was annoying because every immature kid goes through a period of being pessimistic for no reason (and I happened to be in that period of time). However, now I've lost my hatred towards her and really do not hold anything against this coupling anymore. But I do believe that Amelia feels nothing more than a teenage crush for him, and he really doesn't feel anything for her in that way.

Xelloss and Filia:
The only coupling I still resent with a passion even after all these years. Oh. My. God. How many times do I have to tell you that this is NOT a canon pairing? The author never intended it (since Filia was anime-only). The author never intended Xelloss to be paired up at all, actually. It just won't happen. Opposites DO NOT attract in this case. Even with time Xelloss would never develop feelings for Filia. Xelloss and Filia worshippers on the internet are no different from the ignorant Zelgadiss and Lina worshippers running around online. Of course, there are exceptions (whoever can give me a good reason, despite the coupling, will not receive a bashing from me), but many just go with the flow and say "Because they're supposed to be together!" Wake up. Give me a better reason (not stupid ones like "Because purple and gold are royal colors!") or I'll cast you off aside, too. (Note that this is NOT pointed towards the people who really do think they should be together and don't give stupid reasons for their beliefs. I respect your opinions so long as you respect mine.)

Valgarv and Filia:
No problem. It's all fine. Filia might end up as his mommy but she's a relatively young dragon. 100 years is about equal to a 10 year difference in human life. At that time, that wasn't unusual.

Lina and Zelgadiss:
I had a fangirl obligation to Zelgadiss too, at first. He struck me a lot quicker as a likeable character at first (since Xelloss takes time, but usually ends up being a favorite). These two were cool together, too. I'm still rather pro for the Xelloss, Zelgadiss, and Lina thing. Xelloss just took priority when he became my ultimate favorite.

Amelia and Xelloss:
This is one of the stranger alternate couplings I've seen going around. It's also getting more popular by the day with little justification as to why. Personally I don't think it's possible, but I don't think X/L is possible either and I'm all for that, so this coupling doesn't bother me. It's just...odd.

Sylphiel and Gourry:
Now this one I truly concur with. There's only one problem - Gourry and Lina are head over heels for each other. If that hadn't been the case, Gourry should have ended up with Sylphiel in my honest opinion.

Xelloss and Zelgadiss:
Mmm yaoi. Yes I admit to being one of those fangirls with rampaging hormones craving yaoi and anything else good I can get my hands on. These two together amuse me to no end, and I honestly do like the relationship they appear to have with one another. No love, of course, but lust is always fun.

Xelloss and Lina:
We have finally come to the best part...and I've run out of real points to say. There is no real reason why I think this coupling goes together - again, it was originally because of the fangirl instinct. Rather than give the list of stupid reasons why an alternate coupling should have been, I'll just say I like them because they look cool together and I'm very fond of the characters. It just makes me smile to think that, given very different circumstances, they might've had a chance.