In 2034, there was a phenomenon of a sarin gas leak that resulted in many victims. From this incident, the government requires everyone to wear a gas mask. Brenda (F/26), a former military academy student as well as a judo athlete, decided to go to the forest to get away from the city, but Brenda faced a problem due to not having a supply of gas mask filters. Brenda who found information in the middle of the forest immediately approached, but it was not that easy. Brenda had to make an exchange with Toni (M/28) by exchanging rifles, and where Brenda did not allow it, because this rifle was a means of protecting herself. Then Brenda was expelled, because Brenda's ambition was so great she kept trying to get what she wanted, including hurting other people.