In the aftermath of the Monster Rats' sneak attack, Saki and Satoru join up with another group and accompany them to the hospital to check on one of their injured friends. As they arrive, they find the hospital destroyed. After clearing the place of the Monster Rats and rescuing the few survivors, the party is attacked by an unknown individual who kills everyone in its path with an overwhelming power. Fearing that the enemy in question may be an Ogre, the other members of the party decide to sacrifice themselves to let Saki and Satoru to escape and warn the others. However, as they flee along the river, the duo soon realize that they are being followed by the enemy.