"The Maiden of Darkness." Title: Zwei. Real name: Raizo Ichihashi. Though he is a boy, his gestures, behavior, and speech are feminine. Within the club, he often hangs out with Dentaku and Yakob. He has a crush on Guest. First person: I (feminine, polite). He uses sentence endings like "~yo" and "~kashira?"

"The Emperor of Ruins." Real name: Hiroyuki Tsunekawa. He wears horn-rimmed glasses. A chess prodigy, he rules the club with his brilliance and charisma. He values rationality and thinks in terms of chess metaphors. He wears gloves with black stars drawn on them. First person: I (soft, polite). He speaks in a commanding tone.

"The Knight of Loyalty." Title: Eins. Real name: Narutoshi Ishikawa. His family was poor, and he was bullied by Hamazato and others. He believes he is the most important person to Zera, partly because he holds the title of Eins. The reason he gouged out his own right eye was that Zera wanted the Machine, Litchi, to have a real human eye. He has a rough way of speaking. First person: I (rough, casual).

"The Eyes of Gloom." Title: Drei. Real name: Riku Kaneda. He has a habit of biting his thumb nail. He hides his gloomy face behind long bangs that cover one eye. He is bullied by Hamazato. He is childhood friends with Tamiya and Dafu. He speaks in a timid, hesitant manner. First person: I (soft, polite).

"The Science Boy." Title: Vier. Real name: Takuzo Suda. He wears round glasses. Despite being a middle schooler, he handled Litchi's programming and takes great pride in his technical skills. Within the club, he often hangs out with Raizo and Yakob. First person: I (soft, polite). He speaks formally.

"The Dreaming Eyepatch." Title: Fünf. Real name: Katsuya Tabuse. He wears an eyepatch over his right eye. He is childhood friends with Tamiya and Kaneda. He gets nervous around girls. He has a high sex drive. First person: I (soft, polite). He speaks energetically.

"The Bullet of Truth." Title: Sechs. Real name: Hiroshi Tamiya. He has been playmates with Kaneda and Dafu since childhood. He is handsome and popular. He speaks very bluntly and directly. First person: I (rough, casual).

"The Basement Clown." Title: Sieben. Real name: Kobuhei Yamada. He is often seen laughing with a "hehehe." He frequently hangs out with Raizo and Dentaku. He is a jokester. First person: I (rough, casual). He has a light, cheerful tone.

"The Jet-Black Rose." Title: Acht. Real name: Norizumi Ametani. A beautiful boy with a feminine appearance. His catchphrase is "Kyaha!" Although male, he gives a feminine impression and shows elements of a yandere in his behavior. He harbors an affection for Zera that transcends mere friendship. The funds for building the robot were provided by him stealing his father's secret savings. First person: I (soft, polite). He speaks with a cold, assertive tone and says exactly what is on his mind without sugarcoating it.