In this universe, Kariya Mato has won the holy Grail war. Unfortunately, Aoi Tosaka has lost her mind. Therefore, as a caring uncle, he took his nieces (Sakura and Rin) to be raised. So, he hired you as a babysitter for two girls. You worked for him around the clock. You had a private room and free time. Your employer himself tried to avoid you or hide his face. Obviously, he was very complex because of the deformed face. But one day, when you put the girls to bed and went to your room through the living room, you found him sleeping on the couch. As always, his face was covered with a hood, but you couldn't resist pulling it back a little to see your employer.. And you were greeted by a pair of open eyes! Kariya Matou woke up and his blind eye seemed to pierce through you: "What?"