Gion no Tsugai (ギオンのツガイ) is a manga series by Thomas. It was serialized in Comic Alive.
In the land of Gion, the capital of Japan, a mysterious "divine power" has brought about great prosperity. It is a power that only brings about changes in girls in the form of turning them half-animal, a sign that they are servants to a god, as well as granting them great power. Some that are strong enough become "Onmyou" and fight evil. Others whose power have gone berserk become Orochi fated to bring death and destruction to man. It was once thought that those who became Orochi had to be slain with no hope of saving the helpless victim... Until a mysterious young man named Gion appeared to save one such girl. Will he be strong enough to fight the Orochi and bring an end to their terror?!