Seihou Project (which is an actual thing by the way http://en.touhouwiki.net/wiki/Seihou_Project) is a series of Japanese Doujinsoft Bullet Hell games by a doujin circle called the Amusement Makers (with music and art contributed by ZUN). It takes place in a futuristic Sci-fi setting and centers around a "Maid-Type Combat Robot" named VIVIT (later VIVIT-r) who runs errands for her perverted scientist master, Erich. She's later joined by a miko named Hirano Sakurasaki, who first shows up in the third game and in this reality continues to act as player two in later games.

The series has a large cult following in Japan, especially after the jump from PC-98 to Windows, which also came with significant redesigns to VIVIT and Hirano's appearances. The Japanese community is especially well known for large amounts of fanart, Doujins, fangames and fanime they've made for it. The English community has also grown in recent years, though it's not as big.

(I know Eric/Marisa-mun was talking about Es-per-ade or however it's spelled in the last meme of this type, but he didn't know about Seihou, and it's more appropriate as Touhou's replacement in this verse. XD)