A low-ranking researcher who works at the secret evil organization Agastia. She has no interest in refining her femininity and devotes herself single-mindedly to her job in hopes of getting an executive position and becoming a top salary earner. Even though she continues to develop monsters with her ideas that are not bound by existing concepts, she has yet to win against her arch-nemesis Kenshin Blader.

A sad wolf monster that was developed to be a male werewolf, but due to the leader’s final say, it was ordered to have the body of a beautiful girl. However, her brain is still hardwired to be a middle school boy. She’s assigned to the development department and is bombarded with unreasonable requests. She often works together with Kuroitsu and thinks of her as the opposite sex.

The supervisor who oversees Agastia’s development department. He always carries a pair of AR goggles in his white lab coat. He’s pretty much married to his research. He’s usually a cool and relaxed guy, but when he’s under pressure to meet a deadline, he sometimes gets on edge. He’s typically wearing his goggles, but when he takes them off, he’s surprisingly handsome.

The leader of the secret evil organization Agastia. Her appearance and behavior are that of a little girl, but her abilities are the strongest in the organization. She has a habit of doing things without thinking them through, and with just a few words, the organization’s policies and monster concepts are suddenly changed. Kuroitsu is often the one who must deal with these sudden changes.

The chief counsellor and brains of Agastia. He has a lot of charisma and effectively has the power and authority to make decisions regarding the organization's operations. In certain situations, he sometimes disagrees with Kuroitsu about monster developments, but he truly cares for his subordinates. One might say that in a sense, he’s the ideal boss you’d like to have in an evil organization.

The hero of justice. His real identity is Kenji Sadamaki, a young guy who works at a bento shop part-time. He’s generally an honest, sincere, and likeable young man who is burning with a strong sense of justice, but because he’s serious to a fault, he has no idea how to handle himself around women. He’s actually the biological younger brother of Dr. Sadamaki at Agastia.