kams
Artist.
His Touhou works are well known to NicoNico users for parody-style folklore/fables and ZUN-like art. 'Moriya Step' (post #670248) originates from his video.
Artist name: kamS (かむす)
Site name: kam'S
Real name: 武川 克巳 (Mukawa Katsumi) (He never uses his real name on the internet)