Fate/Grand Order氷室の天地～7人の最強の偉人編～•

Fate/Grand Order x Himuro's World: Seven Most Powerful Great Figures Chapter

The source material follows three girls — Kaede Makidera, Kane Himuro, and Yukika Saegusa — at Homurahara Academy, but has nothing to do with the efforts to restore the Human Order. (Source: ANN, edited)