Thousands of years ago, Vampire King Akabara "Red Rose" Strauss lost both his kingdom and his queen. Since humans were unable to kill the queen, they sealed her away, erecting thousands of fake seals so that the king would never find her true location. Despite being pursued by relentless dhampires, Akabara continues to search for his queen to this day...

Akabara's quest takes a sinister turn when an entity called the Black Swan appears. The Black Swan inhabits the body of a young human girl every 50 years, giving her the power to destroy the Vampire King and his queen. With each incarnation the Black Swan grows stronger--will the 49th Black Swan mean the end of Akabara?

This is a spin off story that occurs about 2-3 years before "Spiral - Suiri no Kizuna". One of the main characters is Imari, who is in love with the kid who wants to be a detective, and which also quit school running after Kiyotaka, and it seems he's dating a murderer without knowing it...? But how is it all connected to the blade children? Not long after, our favorite Blade Children from Spiral appear for the rescue, all manipulated by Kiyotaka.
(Source: M-U)

The point of view begins with Hakaze, a witch who ended up on a deserted island. Changing point of views, we now look at Yoshino and Mahiro. Yoshino and Mahiro were best friends, but one day Mahiro suddenly disappeared. Yoshino assumed that he found a clue to whoever murdered his family. Despite the close bond they had, Yoshino has no idea where Mahiro is. However, one day when Yoshino was putting flowers on Mahiros' family's grave, a woman questions Yoshino about Mahiro at gun point. According to the woman, Mahiro got involved with some serious issues that will inevitably put the human race in a catastrophic situation, and the Japanese government is desperately looking for Mahiro. Apparently some sort of "magic" is involved. What happened to Mahiro? And who is this Hakaze girl? What does Hakaze have to do with this? [Mamo]

A supernatural, romantic mystery about Iwanaga Kotoko—a 17-year-old who is cute but smug and wields a cane. She is involved in the supernatural world and solves its problems while trying to win over Sakuragawa Kurou.