In order to return to the free sky, the wings that originally belonged to them were taken away by some evil humans when they changed wings. Half of their power and the qualification to return to the sky were taken away. They could only stay on land, with only blood to prove their specialness. At the same time, while gaining the huge power of wings, humans were forced into dire straits due to the rapid corrosion of their wings. They began to suck the blood of their companions to maintain the wings that would have been impossible to maintain. From then on, they became the vampire clan of the night. One wants to get his wings back, and the other wants to stop his endless blood-sucking career and take away the blood of the original owner of the wings. Can a girl who cannot speak change this fate?