Fate/Stay Night comes up in MoR as the franchise whose Fuyuki City trips up Quirrel in the interrogation*; the ‘Heaven’s Feel’ route is one possible plot in the FSN franchise. Plot summary, ref is probably to evil-Sakura’s ‘army of shadows’, which matches up well with Dementors.
* I looked it up, and Quirrel’s visit there in 1983 or whatever would have coincided with the birth of a few minor characters but nothing else important in the FSN universe, as far as I could tell.
Fate/Stay Night comes up in MoR as the franchise whose Fuyuki City trips up Quirrel in the interrogation*; the ‘Heaven’s Feel’ route is one possible plot in the FSN franchise. Plot summary, ref is probably to evil-Sakura’s ‘army of shadows’, which matches up well with Dementors.
* I looked it up, and Quirrel’s visit there in 1983 or whatever would have coincided with the birth of a few minor characters but nothing else important in the FSN universe, as far as I could tell.