Currently seen as あくあぴっと (aqua pit); formerly 木ノ碕由貴 (Kinosaki Yuki) or アクアビット (aqua bit). Abandoned their old Pixiv account, y_p. In posts labeled 過去絵 (past art), they posted some of their works done on the old account, indicating the connection.
https://www.pixiv.net/users/392287
https://www.pixiv.net/stacc/y_p
https://twitter.com/ykk86
https://twitter.com/intent/user?user_id=1192648542
http://blog.livedoor.jp/y_kinosaki/
https://www.pixiv.net/users/10150267
https://www.pixiv.net/stacc/aqua_vit
https://twitter.com/a9avit
https://twitter.com/ykknskap
http://aquapitvit.blog.fc2.com
http://twitpic.com/photos/ykk86
