Masaya is a university student, but he attends a school that’s not his ideal school. His days are generally gloomy. One day, he receives a letter from serial killer Haimura. He was convicted for nine murders and received the death penalty. Back when Haimura was committing his murders, he ran a bakery store. At that time, Masaya was a middle-school student and a customer at his bakery store. According to the letter, Haimura confesses to having committed eight murders, but he insists that he did not commit the last murder. Masaya begins to investigate the last murder case involving Haimura.
Masaya adalah seorang mahasiswa, tapi dia bersekolah di sekolah yang bukan sekolah idealnya. Hari-harinya umumnya suram. Suatu hari, dia menerima surat dari pembunuh berantai Haimura. Dia dihukum karena sembilan pembunuhan dan menerima hukuman mati. Dulu ketika Haimura melakukan pembunuhan, dia menjalankan toko roti. Saat itu, Masaya adalah seorang siswa sekolah menengah dan pelanggan di toko rotinya. Menurut surat tersebut, Haimura mengaku telah melakukan delapan pembunuhan, namun dia bersikeras bahwa dia tidak melakukan pembunuhan terakhir. Masaya mulai menyelidiki kasus pembunuhan terakhir yang melibatkan Haimura.
