At the end of the Holy Grail War in the ubw line, Emiya Shirou saw Emiya who was about to leave, and his heart was filled with grief. This strong emotion made Emiya Shirou faint on the spot. After waking up, Emiya Shirou became the 48th master of Chaldea, the organization for the survival of humanity. While protecting humanity, he and the amnesiac Emiya healed the demons.
Depending on my mood, it may be updated every year.