nao_(moji)
Artist.
Main nickname: "NAO" or 直 (Nao)
Temporary names for NSFW works: セレンディピティ（仮）or ロドリゲス（仮）
See also
* Pixiv account (main): http://www.pixiv.net/member.php?id=14274
* Pixiv account (NSFW): http://www.pixiv.net/member.php?id=3778835
** Pixiv novels: http://www.pixiv.net/novel/member.php?id=3778835