Full name: Keita Masaki. 36 years old. First person: I (pompous, archaic). Second person: you (polite but distant). Wears a white lab coat. He speaks in a friendly manner, but there is something deeply unsettling about him. He is short with long blonde hair and looks like a woman, but he is a man. At first glance, he appears female, but his voice reveals his true gender. He belongs to the Ikare Research Institute in Bando Prefecture and creates a vast variety of drugs. He occasionally wanders the institute, striking a wooden fish drum while preaching his personal values. He is brilliant but a total eccentric. His favorite food is castella cake. When bored, he passes the time by teasing Dr. Wakabayashi. Signature line: "Sacrifice is a necessary part of medical progress."

Full name: Kyoka Wakabayashi. 29 years old. First person: I (polite). Second person: you (polite). Uses formal language. Taller than Dr. Saito. Wears a white lab coat. She suffers from a lung disease, coughing frequently and occasionally spitting up blood-tinged phlegm. Short black hair. She looks like a man, but she is a woman. At first glance, she is mistaken for a man. It is hard to tell her gender from her voice, but it becomes clear if one looks at her chest. She is popular with women. Calm and composed, she does not show her emotions recklessly like Dr. Masaki. She is a lightweight with alcohol; when drunk, she has a cute side, becoming clingy toward others. She is the most human and sensible member of the group, conducting joint drug research with Dr. Masaki. They sometimes clash due to differing opinions. Her feelings show easily on her face, and when shaken, she breaks into a sweat and occasionally starts to cry.

First name unknown; no one but himself knows it. In his 30s. First person: I (polite). Second person: you (polite/soft). Cheerful and friendly, but he never shows weakness or leaves an opening, leading most people to fear him. Wears a white lab coat. Taller than Dr. Masaki. Has long hair tied back. Male. He holds a high position within the institute and has an impressive academic background. He teases Dr. Wakabayashi (who cannot speak up much since he is her superior). He is the one person who understands Dr. Masaki and served as a mentor to both Dr. Wakabayashi and Dr. Masaki. Because he supports Dr. Masaki, other members of the upper management look at him with suspicion, but he doesn't care. He loves to drink but only gets drunk when drinking with those he is close to.