Mizuki Mizushiro is the author behind the Psycome light novels.
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 say Renko, were to find out that Kyousuke's most important 'Ayaka' is his sister, there'll be hell to pay... Facing dangers left and right, Kyousuke will have to be more resourceful than ever to get himself-and his sister-out in one piece.
Just before the start of summer break, Kyousuke is summoned to Eiri's home. Academy administration readily approves the trip, and he heads home with Eiri! They thought it would just be the two of them, but Renko and Ayaka, after winning parole with their exam scores, decide to tag along. Since the Akabane are a family of assassins, Kyousuke is, to be honest, more than a little uneasy. But they are met with an unbelievably warm reception at House Akabane. Even as the others appreciate the pleasant atmosphere, Eiri is sullen the whole time... The sweet, summery fourth installment of the hardcore love comedy where the more he loves, the more dangerous it becomes. LOVE=KILL!