What should have been a simple day out with friends turns into a mysterious disaster when powerful demonic beasts appear. Kazuya and Atsuro were supposed to meet Naoya, their enigmatic friend, but he doesn't show up and instead sends another friend, Yuzu, to meet them and give them specially modded gaming devices. It becomes apparent that Naoya has given them much more than they bargained for when demons spawn from these devices!
It’s day two of the Tokyo Lockdown with no end in sight. As Kazuya and his friends look for an exit, they rescue a singer named Haru from demons. She gives them a place to stay for the night, but no explanation as to why the demons are after her.