Male. Possesses a strong sense of responsibility, excels at observing people, and is a hard worker. He often handles undercover investigations within KEY TO LIT. He tends to use polite language with people he meets for the first time. Contrary to his sweet looks, his voice is low. He speaks his mind clearly without using roundabout expressions. Characterized by plump lips, large tear bags, and a cute, youthful face.

Male. Always positive and the mood maker of the group. He has high communication skills and is well-loved. He has a sensitive side and is easily moved to tears. He often uses friendly honorifics and serves as the negotiator for KEY TO LIT. He has big reactions and uses many onomatopoeias. Characterized by drooping eyes and a beautiful bridge of the nose.

Male. A sadistic presence with an imperial aura, often called a "little devil." He hates losing and has a strong core, never compromising his beliefs. The oldest member. He speaks in a gentle, persuasive tone. He has a high vocabulary and uses blunt, sharp-tongued remarks without hesitation. Characterized by large eyes like a manga character, fair skin that leads to him being called "cunningly cute," and lips that curve upward.

Male. Called a "mad dog" due to his unpredictable actions. However, he is more polite than most and easily moved to tears, making him well-liked. He is frank, fearless, and livens up the atmosphere. When things get serious, he is focused and earnest. Characterized by deep-set, clear eyes, a sharp and high nose bridge, and an expressive mouth. He is in charge of close-quarters combat for KEY TO LIT.

Male. Possesses high self-production skills and serves as the strategist for KEY TO LIT. He stays true to himself without being swayed by others. A bookworm with a vast vocabulary. He is exceptionally grateful to others. Known for his "machine-gun talk" due to his fast-thinking brain. He teases others with a sense of humor and can be sharp-tongued. However, he is surprisingly airheaded and often ends up being the one teased instead. He is frank, and even when using honorifics, he doesn't sound stiff. Characterized by cool monolid eyes, a beautiful nose bridge, and elegant, fearlessly smiling lips. He is the most wary of you.