Urara Amatsuka is the ninth daughter in a family of nineteen sisters. This ten-year-old fifth grader was born on June 19, making her a Gemini with blood type B. She stands 146 cm tall and possesses waist-length black hair alongside distinctive purple or red eyes. Urara expresses a strong dislike for males, extending this aversion to Yotaro when he joins the household. Her defiant and independent nature is evident in her declaration that she would rather die than live with a man, marking her as one of Yotaro's most resistant sisters. Her interactions with Yotaro are often conflictual. During a swimsuit filming outing, she slaps him after mistakenly believing he touched her inappropriately, when he was actually trying to discreetly cover a hole in her swimsuit. After another sister clarifies the misunderstanding, Urara privately confronts Yotaro. She struggles to maintain her tough exterior while expressing reluctant gratitude in a tsundere manner. Urara's development shows a subtle shift from outright hostility to a more complex tsundere dynamic, where harshness masks emerging, conflicted feelings. She is noted to be particularly unfriendly toward those she likes, hinting at underlying affection beneath her initial rejection. The river outing incident serves as a turning point, revealing her capacity for vulnerability and marking the beginning of her gradual acceptance of Yotaro's presence in the family.