Is this going to be a series then?

Actually, there are only these two from the set on petenshi's site - presumably provided as samples of one of his publications. I don't know where to find the rest of it, and even if I did I probably shouldn't post it all here.

It can be hard to find Petenshi's comics (not as much demand compared to ero doujin?), here are a couple:
http://touhou.wikia.com/wiki/Dr._VERMILION