In the year 2505, human race faced the extinction phase that was feared by everyone. Slowly but painfully, the birth rate fell and the death rate increase. No one knows why. Experts made experiments, researches, trying to find the solution but all failed, along with the hopes of everyone else. The period goes by until the humans left only in two countries that were separated only by a wall built long ago. The countries are called Line and Cell.

The setting took part mostly in Line which was divided by 7 different state-like things named Line1 until Line7. The people were separated by their wealth and names merely because of how materialistic the human have becomes. Living in high Lines were good and fine with large house and plenty of foods, with beautiful clothes and clean sidewalk but not for the low Lines. Crimes are everywhere. Kill becomes usual. Pain becomes ritual. 

In Line, there are 2 different forces that were paid by the people for their entire life security. These 2 forces are Elite/Special force that guards the low Line from Line7 until Line5 and also Police Force that guards the high Line from Line4 until Line2.

The story is about 3 young men who faced a very dramatic situation in life and wanted to devote their lives to avenge it.