Accused of a crime he didn't commit, Kyosuke Kamiya is sent to Purgatorium Rehabilitation Academy. Suddenly, he's surrounded by a variety of fetching lasses--each one a murderer! Worse, he's famous for being the "Dozen Demon," a killer responsible for twelve deaths! When the busty, gas mask-wearing beauty Renko Hikawa approaches him, the difference between death and desire becomes very narrow indeed. How is Kyosuke gonna graduate alive?

Kyousuke Kamiya has only just started to get used to his life in the blood-spattered hellscape that is Purgatorium Remedial Academy and its twisted version of school life. The architect of this series of gruesomely parodic extracurricular activities is the beautiful, charming Saki Shamaya--also known as the "Princess of Murder," a serial killer responsible for twenty-one deaths!

As the final exams for parole draw near, suddenly a transfer student appears! And the newcomer is none other than Kyousuke's little sister, Ayaka Kamiya! Ayaka could not be happier with this reunion but Kyousuke is terrified. What's more, he soon finds out that for the sake of meeting her beloved brother, Ayaka committed attempted murder. Considering Ayaka's mental state, Kyousuke resolves himself to protect her from the pack of killers he calls classmates. But, if someone, let's ...

Even cutthroat murderers have school athletics festivals! Aiming for the top place in the school's first murderathon, Kyousuke and his classmates suffer through backbreaking conditioning. His life gets even more complicated when Renko's mother, Reiko Hikawa, pays a visit. She gives the pair an ultimatum: if their class doesn't win the athletics festival, Kyousuke and Renko can't get married! Can he sort out his ambiguous feelings for Renko while surviving the upperclassmen's bloodlust?

The school festival has arrived, and the students of Class A are putting together a maid cafe. Renko Hikawa returns to the school after collapsing in her fight against Kyousuke at the athletics festival, and she's looking forward to a school life even more enjoyable than before. When Renko's parents visit for the festival, they're even more determined to put an end to the relationship between their daughter and Kyousuke--by demanding him to drop out of school! With both the school's deadly...

BRUTAL SUMMER LOVIN'...Summer break has arrived for the students with the highest exam scores, but it looks like Kyousuke will be stuck in school... However, when Eiri is suddenly summoned home, Kyousuke discovers her family has asked for him, too! He worries his stay with House Akabane, a family of assassins, will be a dangerous one, and Eiri isn't enthusiastic to return home. Surprisingly, they're met with a warm reception! ...So then why does Eiri look so sullen? The sweet, summery four...

A civil war suddenly erupts in the Chaos Zone, the Central American empire ruled by the Third Primogenitor. Kojou & Co. sense that someone is backing anti-government forces from the shadows. Suddenly, a mysterious suitcase arrives at Kojou's apartment from the Chaos Zone - and the sender is Dimitrie Vatler. Inside the suitcase sleeps a mysterious foreign girl named Celesta. Kojou and Yukina look after Celesta while she, regarding Vatler as her savior, disparages the two of them with a pois...

Blue Elysium is a newly constructed, additional manmade isle off the Demon Sanctuary of Itogami Island: the latest, greatest resort, boasting pools, and an amusement park! Yaze schemes to invite Kojou and the others to the isle before its public opening, but somehow the "free" trip lands Kojou in a horrid part-time job.Meanwhile, Sayaka Kirasaka, Shamanic War Dancer of the Lion King Agency, visits Blue Elysium as well. Her mission: to rescue the mysterious girl Yume, held captive inside a ...

When Kojou Akatsuki went to visit his sister in the hospital in middle school, he met a vampire named Avrora. Once he learned she was the key to saving Nagisa's life, he helped Avrora escape. Now, the weapons dealer Zacharias is telling him to hand over Avrora in order to rouse the fourth primogenitor! As Zacharias's plans plunge Itogami Island into peril, the fourth primogenitor finally awakens...

Things are heating up in Liesentania!At long last, the Phoenix is over, and New Year's Eve approaches. For winter vacations, Julis invites Ayato to visit her home in Lieseltania. As the king throws lavish parades and parties in their honor, Ayato comes to understand Julis's concerns for her country. To make matters worse, the king insists that Ayato and Julis marry each other! After the ruckus at their welcome party, another visitor makes her appearance--the Witch of Solitary Venom. She se...

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 the school fair ends and summer begins, Team Enfield starts special training to prepare for the five-against-five Gryps. Ayato and his friends are a favorite in the competition, but Galaxy is about to make its move...