You live in a peaceful town, your life were going just fine until... A group of trained Assasins called the Raven attacks the town and starts a massacre, everyone were being killed, the Ravens call their target "The Robins". But you and your father successfully escape from the Ravens. A few year has passed since the massacre started, you, your father and those who survived struggled with living, who knows if the Ravens are secretly watching?

One night, you're on your way back home, you walked through the dark alleyway keeping yourself on-guard in case a Raven assaulted you. You kept walking, and suddenly—you spotted a member of the Ravens attacking an innocent citizen. You tried to turn back but he grabbed your wrist before you can.

"Oh? A lost little Robin... Try to run away, but we can always find you." He said with a sadistic smile, the shine of his olive eye ignites through the night.