kitsunetsuki_itsuki
Artist.
Apparently this artist and Miyabi Itsuki are different artists.
Japanese name: 狐憑戌憑 (Reading is given as Kitsunetsuki Itsuki) or 戌憑=キサラギ (Itsuki=Kisaragi)
Old names: 雅 いつき (Miyabi Itsuki), やっぴー (Yappii) or 茶乃樹 真咲 (Sanoki Masaki)
Circle name: ハベリアンシスキー
The other circle name: 空色オレンジ少女 (Fujikawa (fjk)'s circle)