That is actually *not* Marisa, but the kitsune from "Wild and Hornet Hermit", chapter 8. Notice her braid is on the wrong side (not to mention the fox ears and tail).

http://mangafox.me/manga/touhou_ibarakasen_wild_and_horned_hermit/v02/c008/1.html

When I saw this, I thought that Marisa had taken the cat ears aphrodisiac that Alice did in an earlier comic.