My opinion: Very much there, I believe it could work (though not as well as a different pairing... you’ll see)

Lets face it, these two are almost always together in the fandom, and there is good reason.

In the anime, the subtext is overwhelming. They are the first two who meet, they even work together for a little while. In episode 11 - just after Heero’s self-destruction in episode 10 - when Quatre asks Duo if he wants to come with him into the desert, Duo says “Yeah, I could use some sympathy.” The colonies havent really betrayed them yet, in fact nothing has happened except Heero’s “death” that Duo would require sympathy about. In episode 19, Heero goes to kill Duo and ends up rescuing him instead. In this same episode Trowa says, “I’m too far away, but Heero will do something for sure.” (correct me if I misquoted that) How exactly would Trowa be so sure that Heero “perfect soldier” Yuy would care? Unless he laerned something about Heero while he was unconcious and then while travelling around trying to get himself shot by Marshall Noventa’s relatives. But I digress.

The subtext from the show continues into endless waltz. Heero and Duo are together for Christmas (and I choose to believe that they were together before that as well). When Heero leaves, it seems to be expected that Duo go with him. There is no discussion between them about time apart or catching up on missed events. Then there is the punch. Heero asks Duo to hit him, and after being appropriately confused, Duo obliges. Heero then immediately responds with a hard punch to the stomach (not the face, which is where Duo punched Heero). As Duo collapses, Heero whispers to him: “Now we’re even, one for one.” My interpretation is that Heero couldn’t hurt Duo - even for the sake of the mission - without it being in response to another action.

My opinion: I think Treize does become emphatuated with WuFei (he seems to like almost anyone beautiful and strong). And WuFei’s post-war into endless waltz obsession is very telling as well. But I doubt it ever happened. The was and WuFei’s honor simply wouldn’t allow such a thing.

My Opinion: It’s there. It is only permissible to split up these two if you insist on following the 1x3/3x1 subtext in the manga. It’s certainly (at the least) an emphaturation on Quatre’s behalf.

My Opinion: In my mind, this is the most stable relationship that any of these three can have. Heero and WuFei alone would fall apart for lack of communication an enourmous emotional scars. Duo and Heero alone would probably end up falling apart - though much more slowly that 1x5 - because Heero’s emotional barriers are too big for anyone (Yes, even Duo-sama) to deal with alone. Duo and WuFei might acctually work... (see below) but I just can’t deny the massive subtext between Heero and Duo.

The subtext is all there. In the manga it is one of the two really obvious pairings (along with 1x3). In the anime, it is strongest while they are in the prison cell, almost dying. In that same part of the manga in fact, they both turn themselves in to OZ (together!). Also, neither of them seems to have emotional scars so deep that they wouldn’t be able to overcome them.