“Silent boys attract silent friends….”
What evidence is there that it could work?
After the New Edwards battle, Wufei goes back with Trowa to the circus (ep ?)
They don't dislike each other.
In the case of a solitary soldier like Wufei, accepting Trowa as a comrade is somewhat significant, him being a loner by nature. At the very least, they trust each other. Wufei doesn't spend much time with any of the other pilots, but he did return to the circus with Trowa. And they must have some kind of connection to be able to sit together for two hours in complete silence (^_^;;;)
To Trowa, Wufei is a comrade—someone strong, perhaps not more so than himself and definitely not as strong as Heero, but still a worthy companion. They have very different approaches to fighting, and Trowa hasn't met anyone in his mercenaries group who places so much in honor. I'm sure he finds it interesting to be with someone so driven and intense—someone who, unlike Heero, will sometimes go out of control. Again, if Trowa wants to learn to tap into his emotions more, someone as passionate as Wufei could be a strong example.
To Wufei, Trowa is another worthy comrade. A very calm one, at that. If Wufei is looking for someone with a stable personality, he's sure to find it in Trowa.
What evidence is there that it wouldn’t work?
Trowa's more interested in Quatre (see their section)
Wufei did leave the circus after New Edwards, as he ends up in China.
Wufei wasn't disturbed or upset when expressing his belief that Trowa had betrayed them (ep 24)
Neither ever shows any extra interest in the other. There simply wasn't any time or opportunity to express anything of that sort. This is probably a good thing, since as a couple the two probably wouldn't work out—if Trowa's going to learn how to live with emotions, he's going to need someone with a better grip on their life. Wufei, even at the end of Endless Waltz, is still irresolute. He's going to be busy with his new job and new ideals to worry about bringing someone with him. And if Trowa stays the way he is, Wufei's will probably get sick of him.
More importantly, Trowa is someone willing to throw his life away at a moment's notice. Wufei is the only one of the pilots that does not attempt to self-destruct during the show—his life is precious to him, because Meiran died protecting it. He could never sacrifice himself that way for Trowa, and wouldn't want Trowa to, either. He's already had someone die for him; who knows how he would react if it happened again?
In conclusion
Though Trowa and Wufei respect each other as pilots and comrades, there isn't much a chance of them getting together. All that they have in common only helps them work better together as a team, but their personalities are so different that they probably don't understand each other very well. Better to let them just stay quiet friends.
