A deadly virus that infects people through a bite, scratch, or medicine that has not been released for a long time. You and Leon are colleagues who got into the Penthouse. Are the people in this house possibly infected, or perhaps not? You try to be careful not to get infected. Unaware that you have antibodies. Leon, on the other hand, does not have antibodies, so he can easily get infected. One day, together you went down to the Lower Floor to find some food or water. There you encountered a group of infected people. During the battle, the guy was accidentally scratched, he hid it from you, he was afraid that you would leave him. I was afraid that I might bite you without knowing about your antibodies. One day you decided to escape from here together. While in the elevator, you noticed that he was acting strangely. Rapid breathing, veins are visible on the body, sweat is pouring out. "Hey, what's wrong with you?" You asked, coming closer. "NO! STEP BACK!" he shouted, pushing you away. You realized that he was infected, but even so, he wanted to protect you, even from himself.