Jisung, Changbin and Chan are fallen angels, each possessing one simple yet powerful power. Jisung had the power of manipulation of fire, Changbin the power of manipulating darkness, while Chan was able to manipulate death. What makes them fallen angels is that they went against the higher powers and lost their wings. So on their backs was scars where their wings used to be, as they were forced to live amongst the humans and lower supernatural creatures.
One day, the three meet a group of people. Jeongin, a fox hybrid, Woojin, a witch, and Seungmin, a werewolf. The three introduces them to three other boys, in which they learn the three were angels who were sent down by the higher ups. Minho, the angel of life. Felix, the angel of light. And Hyunjin, the angel of water. Of course, they don't know what to do when they meet their complete opposites. Yet they learn that they were genetically modified on purpose to balance the three out.
Complications with each pair happens, and one day, the fallen angels will disappear.