TV-Series
Description
Otome Sakamoto is the youngest daughter of the Sakamoto family in the anime Rainbow Samurai, which follows the early life of the historical figure Sakamoto Ryōma. Her story begins on the night of November 15, 1835, near Kōchi Castle, when she is stargazing and spots a comet. That same night her mother, Sachi Sakamoto, is about to give birth. The comet appears to take the shape of a dragon and a horse, and Otome cries out to it, asking that the child being born that night be a boy and promising that she will make him a strong samurai. In response, the comet shifts into a soft glow, and moments later a strong baby boy is born. The newborn is seen as strange because he has long hair on his back, which leaves his father, Yahei, dumbfounded. Otome, however, responds with confidence and purpose, giving the boy the name Ryōma by combining the characters for dragon and horse.

Her role in the family is that of a decisive and devoted older sister who takes responsibility for her younger brother from the moment of his birth. Ryōma grows up as a cowardly and tearful child who is mocked for his back hair and bullied by neighborhood children, and he also struggles as a student, eventually being expelled from his juku, a private school. While others might have given up on him, Otome and the second eldest sister, Ei, refuse to do so and instead raise him more strictly. This decision reveals much about her personality: she is strong-willed, persistent, and deeply loyal to her family, and she believes in Ryōma's potential even when he shows little sign of it. Her strictness comes not from harshness but from a genuine commitment to making good on the promise she made at his birth.

Her motivations are rooted in that promise. Having asked the heavens for a strong son and pledged to shape him into a powerful samurai, she treats that pledge as a binding duty. Her drive to discipline and guide Ryōma reflects a sense of honor and follow-through, as she works actively to build the strength in him that she hoped for. Her key relationships are centered on the Sakamoto household. She shares a close working bond with her sister Ei, and together the two women take on the responsibility of raising Ryōma when others see only his flaws. Her relationship with Ryōma is the emotional core of her role, as she is both the one who names him and one of the primary influences on his early development. Her contrast with her father Yahei, who is simply baffled by the unusual newborn, reinforces her position as a decisive and forward-looking presence in the family.

In terms of development, Otome moves from a girl making an earnest wish upon a comet to a young woman who takes concrete action to fulfill that wish. The arc of her role is consistent: she names the child, refuses to abandon him in his weakness, and commits to raising him with discipline and care. Her notable abilities lie not in combat or physical prowess but in her perceptiveness, her resolve, and her ability to see strength where others cannot. By choosing the name Ryōma and insisting on a strict upbringing, she gives her brother both an identity and a standard to live up to, setting the foundation for the person he will become.