Akito and Yurika from Martian Sucessor Nadesico. Honestly, the way Yurika clinges to him is so horribly annoying. They should have paired Akito with Hikaru, Ryoko, Izumi, Haruka, I don't know, any other woman in the series but Yurika. Heck, I'll even take Erina over Yurika.
On that same vein, Dita and Hibiki from Vandread. The difference is, while I like Akito, I hate Hibiki's guts. The guy's so darn insensible and thickheaded. Dita could do much better if she had any selfrespect at all.
But the absolute pinnacle of wrongness has to be Ed/Al Elric. FOR THE LOVE OF GOD, NO.