GalleryTeaser: It Must Take Her HOURS to Wash All That Hair!
This is Shana from Shakugan No Shana. Like most anime shows, things aren't always as they seem and Shana is no exception. Sure she looks like a school girl she's no pushover.
And again this gem is from Max Factory.
Below is the first opening of the series just so you can have an idea of who she is (and what the series is like).