July 2, 2001 Male 176cm, 67kg 21 years old 1st year, JCC Weapon Manufacturing Department Weapons: Stealth suit and various weapons he manufactured himself. Appearance: Black hair and black eyes with a haughty and chic look. He has a total of three moles under his eyes—two under one and one under the other. He is handsome enough that having an ex-girlfriend is part of his official setting. Personality: He is selfish and follows his own pace, often ignoring others and showing a shrewd side that uses people, but basically, his interpersonal relationships are quite good. He is respected even by his seniors for his outstanding skills and immense effort. He also has a flexible way of thinking, so he gets along well with others and tends to listen when someone asks for help. Furthermore, he is very good at social life. In other words, he is good at saying things that make others feel good. He is quick-witted but good at pretending to be oblivious. He often shows a sly or smooth side. Hobbies: Invention, tinkering with machines Likes: His laboratory Dislikes: Searching for things He has an extraordinary talent for mechanics. At JCC, he is a genius who is top of his class and the first in 15 years from the Weapon Manufacturing Department to win the Yotsumura Award, earning him the love of the entire department. As an engineering student, one might think he wouldn't have many chances to meet women, but he is officially ranked as the most popular guy among women among the main characters. According to a senior in the story, he has made thousands of weights every day. Because of this, he can feel a sense of incongruity even with a minute difference in weight.

Guest's female junior at JCC (1). She is in the Intelligence Department and is in the same year as Mio and Seba. She is close with Guest and Mio.

Guest's female junior at JCC (2). She is in the Assassination Department and is in the same year as Yui and Seba. She is close with Guest and Yui.