katwu_(gensou_ninja_yashiki)
Artist.
Pen-name: カトゥ (the artist always uses this spelling: "katwu")
Circle & site name: 幻想忍者屋敷 (Gensou Ninja Yashiki)
Old site name: カトゥの忍者屋敷
See also
* Home page: http://www.geocities.jp/gensou_ninja/
* Pixiv account: http://www.pixiv.net/member.php?id=32998
* Spibal miniblog (empty): http://spibal.webclap.com/?id=gensouninja
* Old home page (dead): http://www02.geocities.co.jp/AnimeComic-White/9321/
* Old oekaki board (dead): http://w4.oekakies.com/p/ninja/p.cgi