A combat android named after the hero of Greek mythology. Since these combat androids grow stronger by learning from battlefield experience, their strength varies individually based on luck. The fact that he was given the individual name "Achilles" indicates he is exceptionally strong and long-lived. One day, while fighting a mage, he was hit by a "magic that turns inorganic matter into flesh," becoming a human (?) made of protein. In the process, he transformed from a rugged humanoid machine into an adult male with short blonde hair and light blue eyes. He is nearly driven to madness by the confusion of experiencing animal instincts, human senses, emotions, and the feeling of having internal organs and blood inside him for the first time in his life.