saitaniya_ryouichi
Artist.
Japanese name: 才谷屋 龍一 (Saitaniya Ryouichi, the artist uses this spelling: "Saitaniya Ryohichi")
Pixiv nickname: 梅太郎 (Umetarou)
Circle name: ２次元工場 (2Jigen Koujou)
(Other members: Minamoto Taiga and Truffle)
Blog name: 浮いた歯車