Mayumi Tendō is a minor character from the Battle Royale franchise, appearing in the original novel, its manga adaptation, and the live-action film. She is a third-year student at Shiroiwa Junior High School and bears the number 14 among the female participants of the Program. Physically, she is described as an attractive girl with a ponytail, which in the novel is compared to a thick braid resembling a lobster tail. In the manga, her hair is drawn as a long, straight ponytail, while in the film she wears two long pigtails.

Very little is revealed about Mayumi’s background before the Program. In the novel, there is a rumor that she engaged in compensated dating, a practice that caused some classmates to view her negatively. Hirono Shimizu is one of the few who knows this to be true, having seen Mayumi on a date with an older man. In the manga, she is shown as part of Yukie Utsumi’s group, alongside Izumi Kanai, suggesting she was socially integrated and not openly ostracized. The film adaptation alters her characterization significantly: she is depicted as one of the students who bullied Noriko Nakagawa, seen in a flashback locking Noriko in a bathroom stall after writing insults on the walls.

Mayumi’s personality varies across versions. In the novel and manga, she is quiet and does not speak at all during the story; in fact, she is the only student in the manga without a single line of dialogue. She appears composed but is clearly frightened by the situation. In the film, she is more assertive and mean-spirited, fitting the bully role. Her motivations are not explored; like all participants, she is forced into the Program and has no say in her actions.

Her role in the narrative is that of an early casualty. After the students are released from the classroom, Yoshio Akamatsu hides near the school and decides to shoot escaping students with his crossbow. Mayumi is his first clear target. In the novel, he shoots her in the back, making her the first official death of the game. In the manga, the bolt strikes her in the side of the head, killing her instantly. In the film, she is hit in the neck and does not die immediately; as Shuya Nanahara exits the school, she manages to speak a few confused words to him before collapsing. Akamatsu then fires again, this time hitting her corpse in the leg. Her body, along with Akamatsu’s later, is left at the school entrance, serving as a grim warning to the other students that the game is real.

Mayumi has no significant relationships beyond her association with Izumi Kanai and Yukie’s group. She forms no alliances during the Program and dies before any meaningful interaction with other characters. Shuya Nanahara briefly mourns her when he sees her body. She has no character development due to her early death.

In terms of abilities, Mayumi possesses no special skills. Her assigned weapon differs by adaptation: in the novel and manga, she receives a pair of nunchaku, which are later taken by Kazushi Niida after her death. In the film, her weapon is a pair of boxing gloves, which she never uses. She does not survive long enough to demonstrate any combat capability or resourcefulness.