Yeah, an awesome anime, even I feel slightly better than Tsubasa Chronicles. It's D.N. Angel, quite an 'old' anime from few years ago.
It has a very strong opening theme, named True Light.

Daisuke Niwa & Dark. A human with dual personality, some sort of awesome.

Niwa & Riku
Still, I feel weird. I feel really something wrong when I finish the anime. Anyway, I feel envious of the couple. They're so sweet, and sort of romantic though.
Try watching it, if you can...
Mahou Sensei Negima a.k.a. Magister Magi Negima has quite a few cute, really kawaii girls.

Miyazaki Nodoka, a really sweet girl from the anime series. xD Her shy-ness did attract a lot of fans, haha...