Taking place in the year 1937 on the eve of World War II, the story involves a mysterious spy training organization known as the "D Agency." The organization is established by Lieutenant Colonel Yuuki from the Imperial Japanese Army. His ideals lead him to recruit people beyond military academy graduates and personnel, while training them to become skilled agents in arts of manipulation. These agents would become a specialized team to conduct operations. One such antihero agent, under the name Jirou Gamou, goes on a harrowing mission to uncover secret documents titled "Black Notes," while battling forces from within and without his own ranks.

I am Rinceir the Elf, the greatest foodie in the elven world! In the castle town of Farenheit, there appeared a man who pulled a mysterious cart that served a strange new food called "ramen." Each bite tasted heavenly! I quickly became captivated by this "ramen" and waited for him and his cart to come by every night. However, one night, that man I had come to call my "friend" disappeared from my life. Twenty years later, I am still waiting on the same street corner, hoping to see "ramen" again. Oh...... my beloved "ramen", will I ever be able to taste it again......? (Source: Pash Books, translated)

I have a girlfriend, her name is Shiori Hoshino. She is known as the “Ice Emperor” because of her overwhelming appearance and cold personality. And surprisingly, she is an anime fan, and also considers herself an otaku. But in reality she hides a secret, and that is that she has a phobia of men. Although for some strange reason, she usually feels at ease with me. But, there is something that I have not been completely honest with her about. And that is that I maintain a secret relationship with my stepsister. Although, it’s not infidelity if it’s with her, right? Source: NU

A series of one-shots all focused on the secrets people keep from one another and the question "is this person my friend or my foe?."

As he graduated from junior high, Nagito Senda began dating Kiri Asatani, but he got dumped when they started high school. While recovering from his broken heart, he saw Nozomi Takane, a girl in his class, being harassed by a pushy club recruiter, and decided to help her. The two quickly grew closer as they sat together in class and went to and from school together. One day, as the two were cleaning the library, Kiri came up to Nozomi and asked, "Can I borrow Nagi-kun?" When Nozomi asked Kiri about her relationship with Nagito…? "I was Nagi-kun's ex-girlfriend" "Well from now on I'll be his new girlfriend." Now that both girls have declared themselves, what will be his real intention? Sparks will fly in the game between the ex-girlfriend and the current girlfriend. (Source: Kadokawa, translated)

Saint Ilias felt happy that she could help the people of her country with her own power. However, one day, her cousin Marie took everything from her and banished her from the country. Now that she'd been banished, she decided to live a free life unconstrained by any mission! So she set out on a journey in high spirits, only to meet Aktor, the first prince of a neighboring country!? Aktor, who wishes for the prosperity of his country, urged Ilias, "I don't mind giving my all to him! Become the saint of this country!" and Ilias decided to live as a saint once again, but...!? Where will the troubled saint and the prince who supports her go next? (Source: Futabasha, translated)

*"Come on-Which despair do you choose?"* Shiren, a high school student who has both an angel's smile and a devil's plot. The heretical talent shines mysteriously in a game called "PoS" where players fight with each other by making full use of their skills in virtual space. (Source: Dengeki Bunko, translated)

Luna, a saint, was executed by the people she had saved as a fake, ending her life. She was reincarnated 300 years later with immense power, and on her deathbed, she wished to live freely like a "villainous lady." She planned to live quietly and inconspicuously, fulfilling her wish to do so!