It's not easy being popular... In the wake of the destruction caused by the Roses of Tartarus, reconstruction begins on Itogami Island. The people laud Asagi Aiba as their savior, and she's even become something of a local idol. But her boom in popularity is actually a conspiracy by the Gigafloat Management Corporation to cover up the fact that she's being held captive! Catching wind of this, Kojou and Yukina rush to her rescue. But of the many challenges that stand in their way, the biggest seems to be a certain development in Yukina's body...

Kojou and Yukina join forces with Natsuki Minamiya to protect Itogami City from a new threat from the skies--but even Kojou's Beast Vassal can't take this new foe on, and who should rescue them from their predicament but Kojou's sister's friend, a silver-haired girl named Kanon Kanase! But when Kanon disappears, Kojou and Yukina may find that there are some problems not even the world's mightiest vampire can solve!

NO REST FOR A PRIMOGENITOR… It’s a new term at Saikai Academy, and fortunately for Kojou, hehasn’t been held back a year! Freed from his constant work defending Itogami Island, he is ready for some peace. However, an entirelynew demon beast appears, and when Rui and Yuno are dispatched to deal with it, they are gravely wounded. Kiriha forms an unlikelyalliance with Shizuri, who is dead set on avenging her friends. Meanwhile, the Japanese government has concerns about Yukina’s ability to continue observing the Fourth Primogenitor, so the Lion King Agency readies a replacement. As Yukina frets over this threat to her position, her stress only grows with the arrival of a mysterious girl who looks exactly like her!

THE REVIVAL OF THE TRUE FOURTH PRIMOGENITOR IS NIGH! When Kojou Akatsuki was a junior high school student, he met a vampire named Avrora...and then he saw her again when travelling to the hospital to visit his sister. When Kojou learns this mysterious, quiet girl could be the key to saving Nagisa's life, he helps her escape the Magna Atraxia Research lab. With the arms dealer Zaharias planning to use Avrora in his Blazing Banquet, can Kojou stop the revival of the true Fourth Primogenitor and save Itogami Island?

When all the students depart for a school field trip to the mainland, Kojou is delighted to hear that he'll finally get a chance to be free of observation for at least a little while, whereas Yukina has mixed feelings about the whole situation. But events move quickly when an alchemist by the name of Kou Amatsuka appears, with the goal of reviving the holy grail of alchemy--a liquid-metal life-form known as "Wiseman's Blood." As the crisis deepens, even Asagi becomes involved when this alchemist's relic grows more and more uncontrollable. What can the world's strongest vampire do?!

Nagisa has collapsed! Kojou rushes to the hospital, but suddenly a mysterious girl appears, and she looks just like Avrora, the former Fourth Primogenitor. She backs Kojou into a corner--but is she the real Avrora? Through this encounter, Kojou regains his lost memories, what will he remember? Finally, Kojou's past and the secrets of the Fourth Primogenitor are revealed!

After partnering with Natsuki Minamiya to capture the Masked and end the destruction in the sky, Kojou and Yukina are shocked to discover one of the winged girls is none other than Yukina's classmate Kanon Kanase! When Kanon disappears, Kojou and Yukina seek out her adoptive father, a researcher at megacorp Magus Craft, Inc. Far from the professional meeting they expected, the two find themselves abandoned on a deserted island! It is deserted...isn't it?!