Right now, Nega-Yuki has boot workship and sometimes she makes you kiss her feet before she will let you roll her dice.
You do kiss the feet of the Goddess when you first meet her, as well.
We DO have plans for more dedicated feet content, but we want to get in physics to touch Mistresses before we go too far down the foot path! We plan to include foot content with the Giant Goddess, Mistress Yuki-Ona, and potentially a new Mistress, Priestess Caliste.