Artist.
Not sure this artist is the same person as Narimono's artist.

Artist name: 文吾 雪平 (Bungo Yukihira. from the website URL)
Pixiv nickname: ぶんごろ (Bungoro)
Circle & site name: FLATBASE

See also

• Home page: http://www.geocities.jp/bungoyukihira/
• Pixiv account: http://www.pixiv.net/member.php?id=7640