Kaede Marikōji, often referred to by her crewmates as Marikōji-san, is a student aboard the destroyer Harekaze in the Yokosuka Girls' Marine High School curriculum. She serves as a sonar technician, making her responsible for underwater detection and monitoring, and also holds the duty of ship's bugler, sounding signals for the crew. No information is available regarding her background prior to joining the Harekaze.

In terms of her personality, there is no available information describing her typical demeanor or behavioral traits. Similarly, no specific motivations or personal goals are documented for her character. Regarding her role in the story, as a member of the Weapons Department, her primary functions are operating sonar equipment and playing the bugle. While she is part of the ensemble cast that works together to navigate the challenges faced by the Harekaze, her specific individual actions within the plot are not detailed.

No information is available concerning her key relationships with other characters or any personal development she may undergo throughout the series. However, notable abilities attributed to Kaede set her apart from her duties. While she is recognized as an ace in her technical role, she also possesses remarkable skill with a naginata, a traditional Japanese polearm. This proficiency in martial arts is described as a hidden badass quality, and her character design includes elements of a miko, or shrine maiden, which further complements this traditional skill set. Her physical attributes include violet hair, golden eyes, and a height of 1.58 meters.