A Touhou character speculated to have once been playable in The Embodiment of Scarlet Devil, but she was cut before the game's release. A minor reference in the source code of the game are all that's left of her. She's thought to have possibly been a kirin.
Originally thought to be the girl in ZUN's circle cut for Embodiment of Scarlet Devil until it was revealed to just be a random poster girl for Team Shanghai Alice. Unfortunately, nearly all fan depictions of her have used this girl thinking it was Rin.
Well before Ten Desires was announced, two popular rumors in the fandom was that she was a Taoist, due to the erhu, and a nurse like Yagokoro Eirin ("kirin" in Japanese is often associated with white mages). Coincidence?
- Touhou Wiki: http://en.touhouwiki.net/wiki/Rin_Satsuki