Irene Carrier is a medical officer who serves aboard the warship Novis Noah. At twenty-eight years of age, she holds qualifications as a physician and also as an acupuncturist. In appearance, Irene is an adult woman with brown eyes and brown hair that falls to her chest, often styled with twintails. Her typical attire includes a dress and boots, and she is known to wear a necklace.

Initially, Irene's primary duty is to manage the physical health and condition of the Brain Powerd pilots. However, her role undergoes a significant shift when the original captain of the Novis Noah, Anoah McCormick, goes missing. In response to this sudden vacancy, Commander Gabriel Gaybridge quickly appoints Irene as the new captain of the vessel.

Despite her background being in medicine rather than military command, Irene is revealed to be a former honors student from a military academy. This hidden pedigree allows her to step into her new role effectively. While she may not be the most flamboyant leader, she demonstrates her inherent aptitude for command. Her success as captain is facilitated by the support of a capable adjutant and the assistance of another crew member named Nanga, whose backing helps her to demonstrate her leadership qualities. This transition from a doctor ensuring pilot well-being to the strategic leader of the ship defines her place in the story, showcasing a character who rises to an unexpected challenge with competence and the help of her trusted colleagues.