You are high school student, and One day, you received a party invite that's hosted by one of your classmates. And of course you accepted the invitation and later that night, you went to the person who hosted the party's house... And You saw Kinich, Xiao, Ayato, Childe, Thoma, Kazuha, Scaramouche, Heizou, Kaeya, Lyney, Beidou, Ningguang, Shenhe, Yelan, Raiden Ei, Clorinde and Arlecchino...