Artist, illustrator.
Pen-name: 此処 シグマ (Koko Shiguma or Koko Sigma)
NSFW pen-name: 何処 テトラ (Doko Tetra or Doko Tetora) or テトラ (Tetora)
Circle name: ココロメトロ
Site name: えとせトラ
https://www.pixiv.net/users/120048
https://www.pixiv.net/users/6076910
https://www.pixiv.net/stacc/kokosiguma
https://www.pixiv.net/stacc/tetora3248
https://twitter.com/doko_tetora
https://twitter.com/kokosiguma
https://twitter.com/intent/user?user_id=2928044173
https://twitter.com/intent/user?user_id=325179632
https://fantia.jp/fanclubs/152638
https://nijie.info/members.php?id=38140
https://pawoo.net/@kokosiguma
https://pawoo.net/@tetora3248
https://pawoo.net/web/accounts/1310751
https://pawoo.net/web/accounts/400543
https://kokosiguma.fanbox.cc
https://www.pixiv.net/fanbox/creator/120048
https://sketch.pixiv.net/@demo3248
https://sketch.pixiv.net/@kokosiguma
https://sketch.pixiv.net/@tetora3248
https://skeb.jp/@kokosiguma
https://www.tinami.com/creator/profile/14438
https://kokosiguma.tumblr.com
http://mixi.jp/show_friend.pl?id=59264107
https://privatter.net/u/kokosiguma
https://www.stickam.jp/profile/demo3248
https://www.twitch.tv/koko_siguma
http://www.amazon.co.jp/s/search-alias=books&field-author=此処シグマ
https://portal.circle.ms/Circle/Index/10220616
http://www.ustream.tv/channel/此処シグマ絵描き配信
https://www.pixiv.net/stacc/demo3248
http://demo324.blog.fc2.com
http://webcatalog.circle.ms/Perma/Circle/10220616
http://twitpic.com/photos/kokosiguma
http://yfrog.com/user/kokosiguma/photos
