koikei_(koikei)
Artist.
Nickname: コイケイ (koikei)
See also
* Pixiv account: http://www.pixiv.net/member_illust.php?id=143204
* Niconico account: http://www.nicovideo.jp/user/453958
* Niconico Seiga (empty): http://seiga.nicovideo.jp/user/illust/453958
* Twitter account: https://twitter.com/koik9999