Itsuka Tenma No Kuro Usagi!
Himea is an awesome and unique character. She's sweet but not a push-over. She's clingy but not annoying. She's dedicated and protective but not a yandere. But if you hurt her man Taito, (not flirt with him but actually HURT him)
she WILL kill you.
She is also the most gorgeous female anime character I've ever laid eyes on. Her hair is three different colors.
THREE. And it sparkles like diamonds. Seriously. XD
A lot of people disliked the show because "omigod it didn't follow the novel!"
but I didn't read the novel and I loved it. And if you want a pretty, romance anime where a tsundere doesn't win, I think it's a nice choice. Actually, there are no female tsundere characters in the series at all.
.........also I'm surprised NOBODY mentioned
Kanon or
Air!?