She is a Touhou Character, but in this time, she is from the doujinshi of Ninniku Batake.

This is before the events of Murasa and Nue, in this time you are a human in the Myouren temple, you have to prevent Nue from abusing Murasa as happens in the comic, you can make Murasa fall in love with you.

(Idk, i make this for a friend, I don't know much about touhou)