The Heat Haze Daze (カゲロウデイズ Kagerō Deizu), also known as the Kagerou Daze, is a never ending world, created by Azami.
- The Heat Haze Daze is a never ending world, created by Azami, who originally intended to live in this world with her family, due to the fact that humans age much faster than gorgons and would mean that her husband Tsukihiko, who was a human, would have to die long before her time. However, their home was attacked by the villagers immediately upon creating it, so she came to believe that unhappiness comes when she is involved with humans. She ultimately decided to enter the Heat Haze Daze alone and live there in eternal solitude.
- However, time passed and her daughter Shion, as well as her grand-daughter Marry were murdered by humans and swallowed by the Heat Haze Daze. Wishing for at least her grand-daughter to live, Azami gave her the Queen of the Snakes, also know as the "Snake of Combining Eyes", which would serve as a surrogate life for Marry, while Shion lost hers.
- Azami lost her ability to unite the snakes, so she became unable to undo the order she gave to the Heat Haze Daze: "Bring in the people who died on August 15 (the day of Marry's death)". To enter the Heat Haze Daze, a living creature must die on that date. It is possible that one of the snakes possesses them, acting as a surrogate life and making them receive an eye ability, which makes it possible for them to leave the Heat Haze Daze again, while in some cases they do not receive a snake and remain inside the Heat Haze Daze.
- Countless black snakes with deep red eyes grow from Azami's head as her hair, which is a typical feature of a gorgon. These snakes, however, are intelligent creatures on their own, the most intelligent one being the Snake of Clearing Eyes, which is the snake that gave Azami the idea of the Heat Haze Daze in a dream she had. As Shion and Marry were murdered by humans and swallowed by the Heat Haze Daze, Azami gave Marry the Queen Snake, which is able to control all the other snakes, so she would be able to make it out again. The loss of their queen Snake enraged the snakes enough to make them overthrow Azami under the lead of the Snake of Clearing Eyes, as she was no longer able to control the never ending world without it. Since the Queen Snake would now live in the real world, the snakes planned to possess the bodies of humans who entered the Heat Haze Daze, in order to follow their queen and create a new medusa/gorgon in the outside world.
- There are several named snakes in the series, who possessed the bodies of humans:
- Queen Snake / Snake of Combining Eyes: Marry Kozakura
- Snake of Concealing Eyes: Tsubomi Kido
- Snake of Stealing Eyes: Kousuke Seto
- Snake of Deceiving Eyes: Shuuya Kano
- Snake of Captivating Eyes: Momo Kisaragi
- Snake of Opening Eyes: Takane "Ene" Enomoto
- Snake of Focusing Eyes: Hibiya Amamiya
- Snake of Awakening Eyes: Haruka "Konoha" Kokonose
- Snake of Clearing Eyes: Kenjirou Tateyama, Black Konoha, Hiyori Asahina
- Snake of Favoring Eyes: Ayano Tateyama
- Snake of Retaining Eyes: Shintaro Kisaragi
- Although the Snake of Staring Eyes has been shown to give Azami the ability to turn people into stone, it did not possess Shion nor Marry to make it possible for them to use similar abilities, as Shion could turn people into stone (although requiring too much energy for her to handle) and Marry can temporarily paralyze anyone who looks into her eyes.
|Involved||Cause of Death||Image|
|One day, her father's business went bankrupt. It drove him to set their house on fire, and the entire family was swallowed by the flames. Kido came into contact with the Heat Haze Daze, along with her sister.|
|During his childhood, Kano went back to his apartment, after spending some time outside, and found the door unlocked. Thinking that his mother was home, Kano went inside the room, only to have found that his mother was tied up and two men were taking her jewelry. Shocked by the event, Kano tried to take the jewelry back, since he knew that his mother had worked hard to get them. However, he was overpowered by the men. When they were about to kill him, his mother took the blow. Shaken, Kano continued to resist the men, but he too, was stabbed.|
|On a stormy day during his childhood, Seto witnessed some children trying to throw his dog friend into a river. Despite his efforts, the dog was thrown in and Seto jumped into the river in order to save it. They both ended up drowning.|
|One day while Marry was playing outside against her mother's warnings, she was found by humans and almost kidnapped. Shion found her in time to turn one of the attackers into stone, but before she could use her ability on all of them, it was too late and both of them were killed with some sort of blunt object.|
|Momo was visiting the beach with her father when she got caught by the waves and drowned, resulting in her death. Her father drowned with her in an attempt to save her.|
|Takane Enomoto||During high school, she lost her life when someone administered her with a drug. Through a window in the dark she was able to spot her teacher Kenjirou, who did not only have her body connected to an unusual machine, but also Konoha's, who was placed in a tank of some kind. Before being able to figure out why Haruka's video game character lived, she touched the window by accident and began to disappear.|
|Shintaro Kisaragi||Route XX: Instead of meeting the Mekakushi Dan, Shintaro remained at home, grieving over the loss of Ayano. Ene begged him to bring himself out of his sorrow and go outside, but Shintaro refused to listen to her. Eventually, he became angry and annoyed with her, which led him to get rid of her. After this, Shintaro fell into greater despair, and commited suicide by slitting his throat with a pair of scissors.|
|Hibiya and Hiyori got caught in a traffic accident during summer and were both swallowed into the Heat Haze Daze.|
|Haruka Kokonose||In his second year of high school, he suffered a sudden stroke and lost his life. In the Heat Haze Daze, he met Azami and was presented with a new body - the body of his video game character, Konoha. Haruka denied the body, but was forced to accept it and had his memories erased as a result.|
Ayano Tateyama (Manga only)
|Kenjirou researched the Medusa's ability together with his wife, Ayaka, when they were caught in a landslide in the middle of it and lost their lives.|
|Ayano Tateyama||After the death of her mother in the landslide, she discovered that the "Legend of the Medusa" is not just a tale, but a real phenomenon, and that her father was possessed by one of the snakes. After figuring out that the snake was following her father's wish to see her mother again and therefore planned to use those who died at August 15 to be possessed by the snakes of Azami, in order to gather around a queen snake and create a new medusa in the real world, Ayano grew increasingly concerned for the safety of her adopted siblings and involved friends from school. In order to stop her father and the snake from reaching their goal, she jumped off the roof of her school and came in contact with the Heat Haze Daze, planning to gain an eye ability and stay inside of the Haze, so the snakes could not gather in the real world.|
- The locations where each character is shown for the first time in the anime are the locations of their individual death, excluding Marry.