The artist linked an earlier tweet of theirs in the replies to this one, which translates as something like:
Happened upon this.
There's a theory that the "kuta" part of "kutakake" (chicken) comes from the Ainu-Itak "kotan" [TL note: village]. If that's the case, then could Kutaka Niwatari, in the world of Touhou where ainu influence is thin, be connected to the ainu?