The original song is Flowering Nights, Izayoi Sakuya's theme.

Touhou is a Japanese doujin game series focused on "Danmaku" or bullet hell shooters. The original theme is played in the 9th Touhou game, "東方花映塚 ～ Phantasmagoria of Flower View"

Someone actually found the picture thanks Hyper Nuclear Engine X20A duder https://danbooru.donmai.us/posts/58034 https://www.pixiv.net/member.php?id=885814 (artist)

Download link (fixed [its not a virus i swear]): http://www.sendspace.com/file/gouv9l