Gilgamesh, the half-divine King of Uruk, was regarded as a mere fable... until his magnificent tomb in the Middle East was unearthed This imperial crypt brought scientists from all over the world to the region, and with it came acclaim for their achievements. They collaborated to build Heaven's Gate in order to further human understanding. One day, a group of terrorists motivated by avarice assault Heaven's Gate, resulting in an explosion within the archaeological dig complex. The emerging event has far-reaching consequences that no one could have predicted. It especially caused the birth of supernatural entities. In the middle of this chaos, two siblings named Kiyoko and Tatsuya come upon intriguing men with extraordinary abilities who, despite the scientific disaster that surrounds them, continue to exist.