Duo and Trowa
Well Duo is a very slashable character, he's got that easy charm, and seems to flirt with everybody, but you don't see much 2x3 for a reason, I think. Truth is, if you wanna talk about opposites, you gotta look at this couple. More so than Heero, Trowa cancels out Duo's personality with his own. For instance, Duo strikes me as (and this isn't a knock against his character) very self-centered, while Trowa is very self-sacrificing. Don't even try to say Duo doesn't worry about his image (Shinigami, the riding pants, *and* the braid?) while it's obvious Tro doesn't seem to put much stock into what he looks like. (Though I'm forced to wonder if he's not trying to show off his ass in those jeans.)
But, it could happen. Duo has a lot of acquaintences but it wouldn't surprise me if he didn't count too many people as his friend. Trowa is someone Duo could trust, and open up to. Also, Trowa's devotion would probably just what the doctor ordered for this twice orphaned American. I think Trowa could very well be attracted to Duo's obvious physical qualities as well as want to vicariously experience the fun-loving, careless attitude Duo exudes in his less angst-ridden moments. Duo's forward enough to break through the protective shell Trowa's created, and experienced enough with trouble childhoods not to be put off by Trowa's past.
Would it work? Probably not. True opposites rarely get along when you talk about long term. They'd both have to make a lot of concessions for each other, and I don't see them doing it. Duo doesn't seem like the type to stick around things that make him unhappy, so when things started cooling down (yeah, I see a great sexual chemistry there) he'd probably let Trowa down with a well-choreographed speech of cliches ("It's not you, it's me") and then move on. Likewise, Trowa doesn't seem like the type to work with relationships, so I doubt he'd convince Duo to try and make it work.
Not to say anything against the pairing. I'm all for it, angsty, sappy, fluffly, lemony, it doesn't matter so long as it does the two character's justice. Going by the book, (or rather, by the series) I don't see it happening, and if it did happen, I don't see it lasting, but that's not set in stone.
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