Artist.
Artist name: ６羊 (reading is given as ひつじ, Hitsuji)
Site name: 夢風船
https://seiga.nicovideo.jp/user/illust/19951370
https://www.nicovideo.jp/user/19951370
https://www.pixiv.net/users/2967369
https://www.pixiv.net/stacc/6hituji
https://twitter.com/6hituji
https://twitter.com/intent/user?user_id=710674716
http://twitpic.com/photos/6hituji