lily_white said: So now that leaves the question, "Who is this guest artist named Utaroku and do they have a Pixiv account or Danbooru tag?"
Going to his site link and clicking the "About" link reveals a Pixiv link at the bottom of his profile. His Pixiv user name is still Utaroku, but directly viewing one of his images shows his registered ID as "uta6". Neither turns up in a tag search on Danbooru.
So the answers, in order are: An artist friend of Bkub's, yes, and no.
My name's Yukari! I'm 16, and I live on love and sweets! I'm totally at the height of my youth right nowww!★When yours truly, Utaroku, was told before by Mr. Bkub I gave the impression that Touhou was nothing but drawing Reimu, it was a terrible shock.Yeep!Ohhh, darn it, I'm late, I'm late!Chp
Chp
Chp...OwwwwI'm sorry.I'll come home.Campus Love ApocalypseWhammmJeez! Watch where you're go-...Thank you for purchasing
★ Cafe de Phantom.EndI resolved in my heart that the next time I was a Touhou guest artist, I'd draw Youmu, and so I did. (The stuff at left is a bonus.)