Gojouno Kaguya is a character from the Astraea Familia, serving as its vice-captain. She is a human hailing from the Far East, where she was born into the noble Gojou House, a family charged with protecting the laws and justice of the Imperial Court. As a member of this family, she was forced to carry out dark assignments, including the killing of innocent people by order of the court. A pivotal tragedy occurred when she was twelve years old, as the Rokujou House, which included a boy she had feelings for, attempted a coup. Kaguya refused to kill him, as she did not believe it was just. In response to this betrayal of her duty, her patron deity at the time, the goddess Konohanasakuya-hime, used her charm ability to override Kaguya's will, forcing her to kill the boy herself. After the incident, the goddess released her falna, and a deeply traumatized Kaguya left the Far East.

Upon arriving in the labyrinth city of Orario, Kaguya became fascinated by the goddess Astraea and joined her familia. She proved to be a highly talented adventurer, ranking up quickly and becoming a famed member of the group. As part of the Astraea Familia, she participated in the Great Feud, helping to defeat the powerful adventurer Alfia and reaching Level 4 at the age of seventeen. Her personal philosophy often clashed with that of her younger comrade, Ryuu Lion. Kaguya believed in saving the masses over the few, holding that it was impossible to save everyone and that every person would eventually be forced to make a difficult choice. This utilitarian view led to frequent arguments between her and the more idealistic Ryuu.

In terms of personality, Kaguya presents a striking duality. On the surface, she appears graceful, composed, and elegant in her words and actions, fitting for a woman of noble birth. However, this façade quickly gives way to her true nature, which Ryuu describes as foul-mouthed and thoroughly unrefined. Kaguya is known to act without concern for social norms, such as stripping down to her underwear when she feels hot, even in the presence of men. Despite her difficult past, she is utterly devoted to Astraea, whom she deeply admires. She maintains a fierce but friendly rivalry with Ryuu, constantly competing with her to advance faster as adventurers and sharing combat techniques with her. The two are close, and Kaguya’s attitude and fighting style have a significant influence on the young elf.

Kaguya is an exceptionally skilled fighter, recognized by Ryuu as the strongest hand-to-hand combatant in the Astraea Familia, proficient in both unarmed combat and swordsmanship. Her abilities stem from her bloodline, as the Gojou family has perfected secret killing techniques over a thousand years. Her primary weapon is a katana named Higanbana, which she wielded with devastating iai, or quick-draw, techniques. These include Issen, a single powerful drawing strike, and Futaba, a technique using dual kodachi short swords. Her signature ability, Gokou, is both a magic spell and a technique. As magic, it creates five blades of magical power that surround and trap an enemy. The ultimate secret technique of her family, Iai no Tachi Gokou, combines her magic with her sword-drawing to unleash five incredibly fast slashes. She was also the original owner of the twin kodachi named Futaba, which she later bequeathed to Ryuu.

Kaguya’s story comes to an end five years before the main events of the series. The Astraea Familia was lured into a trap within the dungeon by the Rudra Familia. Though they survived that attack, the resulting destruction in the dungeon spawned a powerful, supernatural monster known as the Juggernaut. To allow Ryuu to escape and survive, Kaguya, alongside her captain Alise Lovell and fellow member Lyra, made the ultimate sacrifice, staying behind to fight the Juggernaut and giving their lives to defeat it. Her death, along with the rest of her familia, has a profound and lasting impact on Ryuu, shaping the person she becomes.