It should be "templates," not "context." And I have no idea where that meme started. Somewhere with Touhous involved.
Ennui Akadako's Inumiko. Ennui Akadako was one of my favorite circles way back when...
Reimu is turned into a chibi inumimi, and Marisa asks how such an absurd setup came to exist, and Reimu responds by pulling out a chalkboard with the memetic options written on it, and says "Pick one?," to which Marisa responds with the memetic response.
The credits page gives the "Publication date" as "May 21, 2006". FWIW, the hard translation seems to have taken from October 2006 to February 2007, going by the modification dates of the jpegs.