What happens when the world becomes too overpopulated and the most powerful nations decide the only solution is mass-murder? When Luhan returns to China to receive confirmation and safety, he instead is confiscated, and Minseok is forced to uncover the government's secrets in hopes of saving his best friend before he's murdered, if it's not already too late...

The population is at seven billion, steadily continuing to rise daily. Poverty, homelessness, unemployment, sickness, and other miseries are increasingly taking over many people’s lives. Environmental stability is becoming impossible.

To solve these problems, the United Nations have come up with a way to decrease the population – by killing one-half of the world's citizens. A list of seven groups is published - called Categories - stating who is qualified for death. A clock keeps track of the number of people who are confiscated, and will not stop until the counter hits three-billion five-hundred million. After this point, the obtained members of society will be executed and disposed of, thus leaving a more bearable number of people on the Earth.

However, the government is keeping secrets about their body count...

Kim Minseok lives in South Korea, working as a barista at a reasonably well known coffee shop. He doesn’t fall under any of the government-listed Categories, but he still lives in fear worrying he might mistakenly get killed.

He works with Kim Jongin and Do Kyungsoo, two opposites. Jongin is, at very least, a Category 5 – a drug abuser. (He might also fall into Categories 2, 3, and 4. If he has a home or a family, Minseok hasn’t heard of either. Minseok also doubts he fears death. Jongin has not been caught yet.) Kyungsoo, meanwhile, clears the Categories and is confident in himself. He comes from a nice, clean family, and has already been cleared as safe from death. He doesn’t like Jongin because of his drug abuse and poor work ethic, and now because he is a Category. Death by association isn’t unheard of.

Luhan is a friend of Minseok’s - his best friend. They met through Minseok’s work, Luhan a regular coffee (or rather, bubble tea) drinker and customer of the café. Luhan lives in Korea on his own, but has family in China, so he too is safe from the Categories.

However, when Luhan returns to China for his Confirmation house call, he is confiscated as a Category 9, and Minseok is forced to uncover the government's secrets in hopes of saving his best friend before he is murdered, if it's not already too late...