Indeed, that's Lu Xun (Rikuson, to the Japanese tongue). The pic is the cover of a Dynasty Warriors doujinshi by U.R.C./Momoya Show-neko called "Rikuson-chan to Fude" ("Lu Xun-chan and the brush").
It's one of a series of doujin U.R.C. did that features Lu Xun, genderswapped due to a curse Zhang Jiao placed on him/her, and ending up in a sexual relationship with Gan Ning.
