TV-Series
Description
Raiha Uesugi is the cheerful, honest, and friendly younger sister of Fuutarou Uesugi, contrasting his serious and blunt nature. Due to family circumstances, she shoulders significant household responsibilities despite her youth, managing finances via a daily cashbook and handling most cooking and chores, sacrificing typical childhood activities. Her notable culinary skills earn admiration even from Nino Nakano, the most skilled cook among the quintuplets. Raiha also cuts Fuutarou's hair, though limited to simple styles.

Physically slim and of medium height, Raiha has long dark hair typically styled in a high ponytail secured by a simple butterfly-shaped ribbon. Her eye color varies between adaptations, appearing blue in the first anime season and shifting to amber in later seasons; some sources describe them as green or brown. She commonly wears overalls or, during middle school, a blue sailor-style uniform with a yellow ribbon.

Raiha shares a close bond with Fuutarou, who is motivated by a desire to improve her life. She openly expresses both criticism and affection toward him, acknowledging his flaws while highlighting his positive qualities. Among the Nakano quintuplets, she develops particularly strong connections with Itsuki Nakano, who frequently visits their home to share meals and cooking, and Yotsuba Nakano, who wishes Raiha were her own sister. Raiha often acts as a peacemaker during conflicts involving her brother and the sisters. Her perceptiveness allows her to understand complex family dynamics and leverage situations advantageously, occasionally using her charm or expressions to influence outcomes.

Her background includes transitioning from elementary to middle school during the series. The Uesugi family's financial constraints necessitate her early adoption of domestic management. Key events involve organizing wake-up routines for Fuutarou to prevent tardiness and experiencing health issues like fainting from fever, prompting Fuutarou to prioritize her care. In later storylines, she appears as a high school student attending Fuutarou's wedding, assisting by delivering the forgotten wedding ring.

Within expanded media like visual novel games, Raiha joins the Nakano sisters and Fuutarou on trips, including a summer vacation to a private island where unexpected circumstances extend their stay, and a graduation trip to Okinawa. She participates in group activities and interacts with all quintuplets, sometimes guiding story elements in promotional materials. Her personal interests include a fondness for hamburger steak, orange juice, penguins, zombie movies, encyclopedias, and visits to game centers, though she dislikes tomatoes. Her name derives from "Raijin" (thunder god), complementing her brother's name meaning "wind god."