Fate/stay night: Heaven's Feel II. Lost Butterfly.

Shirou has lost his Servant, Saber, and is no longer a Master in the Holy Grail War. Despite this, he refuses to leave the battle, determined to protect Sakura. Meanwhile, a mysterious shadow engulfs the city, killing Masters and Servants one by one. As Shirou faces new dangers, Sakura is drawn deeper into her own destiny as a mage.