Nagihiko Fujisaki, also known under his female alias Nadeshiko Fujisaki, is a main protagonist in Shugo Chara! Party!. He is a student at Seiyo Elementary School and a member of the school's Guardian student council. His background is rooted in a family tradition where male children are raised as females and trained in the art of oyama, male actors who perform female roles in kabuki theater. As a result, Nagihiko spent much of his early life presenting as a girl named Nadeshiko, wearing girls' clothing and using a feminine name. This upbringing was intended to help him understand the footwork and posture of female dance, a crucial skill for his family's kabuki heritage. He later reveals his true male identity and begins attending school as Nagihiko.

Nagihiko is graceful, calm, and somewhat enigmatic, often maintaining a poised and friendly demeanor. He is supportive and looks after his friends, particularly Amu Hinamori, for whom he shows a caring and protective side. He is also known to be playful and occasionally mischievous, such as when he tried to bribe Amu with photos to convince her to join the Guardians. After returning from studying dance abroad, he becomes more confident in his own identity and embraces his role as a boy, showing a friendly and optimistic personality.

His motivations are tied to his personal growth as a dancer and as an individual. He initially struggles with the pressure to uphold his family's traditions and the loss of his first Guardian Character, Temari, who returns to her egg when he loses confidence in his dance performance. His desire to pursue his own rhythm and passion for basketball leads to the hatching of his second Guardian Character, Rhythm. He seeks to balance his family's expectations with his own true self, ultimately finding fulfillment in both his dance and his friendships.

Nagihiko initially serves as the Queen's Chair of the Guardians under the guise of Nadeshiko. After his true gender is revealed and he returns from his dance studies in Europe, he takes on the role of the interim Jack's Chair, filling the position left by Kairi Sanjo. He actively participates in the Guardians' duties, including searching for and purifying X Eggs and X Characters, and later mentors new Guardian apprentices. In Shugo Chara! Party!, he continues to support the team and develops his abilities further.

Nagihiko has close relationships with several key characters. He is good friends with Amu Hinamori, offering her emotional support and advice in her love life. He shares a trusting bond with Tadase Hotori and Kukai Soma, who are among the first to learn his secret. He also develops a friendly dynamic with Rima Mashiro and others in the Guardian group. His Guardian Characters are Temari, a pink egg representing his traditional dance training, and Rhythm, a blue egg representing his love for sports and freedom.

Nagihiko undergoes significant development. Temari withdraws into her egg when Nagihiko doubts his dancing ability, but she later returns after he regains confidence. During his time abroad, he begins to embrace his true male identity and, upon coming back, openly attends school as Nagihiko. The emergence of Rhythm marks a turning point, as he rediscovers his passion for basketball and learns to move at his own pace. He masters the ability to Character Change with both Temari and Rhythm, and later achieves Character Transformation.

Notable abilities include his skill in traditional Japanese dance and his proficiency with two distinct Guardian Characters. When Character Changing with Temari, Nagihiko adopts a fierce, battle-hungry personality, speaking in Hiroshima slang and wielding a naginata. Temari initiates the change with the phrase "Chin, Ton, Shan." When Character Changing with Rhythm, he becomes highly athletic and adept at various sports, especially basketball. His Character Transformations are Beat Jumper with Rhythm, using attacks such as Beat Dunk and Blaze Shoot, and Yamato Mai Hime with Temari.