Forest of Tohno. Yeah, the one from SoEW. For some reason I adore the simple, lonely feel of this theme. It's fitting because even though Reimu has won, she has nobody to celebrate it with, because even her best friend isn't her friend yet. Honorable mentions go to Shinto Shrine (MS bad ending theme), Darkening Dusk (SWR ending theme) and Youkai Temple (UFO ending theme).