https://www.pixiv.net/users/27792
https://www.pixiv.net/stacc/yuuduck
https://twitter.com/yuuduck
https://twitter.com/intent/user?user_id=64682601
https://seiga.nicovideo.jp/user/illust/182928
https://dic.nicovideo.jp/u/182928
https://www.nicovideo.jp/user/182928
http://yuuduck.blog.fc2.com
https://ch.nicovideo.jp/community/co47993
https://com.nicovideo.jp/community/co47993
http://yfrog.com/user/yuuduck/photos
