Description from original post (created 2012-05-16 12:16):
Sanae is a character from the game, Touhou10, Mountain of Faith. 
She later reappears as several bosses and is a reoccurring playable character. Many fans portray Sanae as the Luigi of the Touhou world, where Reimu Hakurei is Mario. Even their color fits the mario world, where Reimu is mostly red and Sanae is mostly green.
Sanae is the shrine maiden of the Moriya Shrine. When her shrine begun to lose faith in the real world, her shrine's actual deity, Kanako decided to move the entire shrine to Gensokyo, where at least yokais will have faith in her shrine.
Her hair clip seemed weird in the previous upload, I changed it a little.