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Midori Days if you're looking for something short (I think it's like 12 episodes). Basically a girl has a crush on this punk boy but could never bring herself to confess, and then one day she magically ends up replacing his right hand (you read that right), and they get into wacky hijinks trying to figure out how to deal with their new living arrangement. Sounds like a horror story or fantasy-heavy with that premise, but I assure you it's wholesome fun.
Eureka Seven (but not the sequel or the alternate universe movie, and not even the manga) if you want something longer (I think close to 50 eps), and want some action/mecha to mix things up between the romance.