Claymore, Shikabane Hime: Aka Recommendations
Both anime have strong willed supernatural characters that has to rid the world of their own kind (in Claymore, its demons rather then undeads). Both feature the main characters "employed" by a larger organization and both has respective handlers for each fighter.
Both has a badass female who is human and yet not human, who has a sidekick she hides her emotions from.
There are many similarities in both of these series.
It's as if Shikabane Hime is more of a modern-day version of Claymore, the only differences are that the "monsters" are different as in name and looks, but other than that they're very similar, and there are other differences too.