The Unleashing was the feared consequence of a failed Tattoo Priestess. Once the tattoo spreads into the priestess’ eyes, it act as a mirror, reflecting all the pain and sorrow back into the real world. This intense emotion caused the gates of the underworld to open, allowing the Rift to spill out. This catastrophic event was caused when Reika Kuze, distraught by witnesses the murder of Kaname Ototsuki, allowed the tattoo to enter her eyes. Once the Rift began to spill out, it began to corrupt everything within its path.
Unlike the Malice and Darkness, the Rift is slow moving and does not kill instantly. Yashuu Kuze, who was in the direct contact, didn’t begin to see effects until a few weeks later. She ordered the Shrine Carpenters to seal away the shrine in hopes of preventing the Rift from progressing. This plan did work to an extent, but the lasting consequences remained.