Inoue Orihime is a central character whose presence and depth grow significantly throughout the narrative. She is a high school student living alone in Karakura Town, having experienced a profoundly difficult childhood. Raised in a dysfunctional family with neglectful and abusive parents, Orihime was taken away by her older brother, Sora, who was fifteen years her senior. He became her primary caregiver and raised her on his own. Tragically, Sora died in a car accident when Orihime was nine years old. After his death, she lived in an apartment complex under the financial support of a relative but took care of the household by herself. As a tribute to her brother, she always wears the two flower-shaped hairpins he gave her on the day he died, never removing them except to sleep. Her distinctive long hair is also a symbol of friendship and gratitude, grown out in honor of a promise made by her best friend, Tatsuki Arisawa, to protect her.

Orihime possesses a warm, friendly, and exceptionally kind personality. She is notably sensitive and empathetic, often putting the well-being of her friends and loved ones before her own. Her demeanor is typically cheerful and gentle, though she is also famously naive and absent-minded, which stands in stark contrast to her academic performance; she consistently ranks as one of the top students in her class. This air-headedness, combined with a wildly overactive imagination, often leads her to create bizarre scenarios in her mind or invent strange new sports, serving as a source of comic relief. Her culinary skills are also a running joke, as she creates unusual and often unappetizing dishes that only a few people, like Rangiku Matsumoto, find appealing.

As the story progresses, Orihime's character undergoes significant development, transitioning from a happy-go-lucky girl to someone who struggles with deep-seated feelings of inadequacy and inner turmoil. She has low self-esteem and often views herself as a burden to Ichigo Kurosaki and their friends, feeling helpless because she believes she lacks the combat prowess to fight alongside them effectively. This stems from a strong desire to protect others rather than needing protection herself. Her primary motivation becomes the wish to support Ichigo and prevent him from having to fight alone, even if it means sacrificing her own safety and happiness. She is acutely perceptive of the emotional states of those she cares about, especially Ichigo, and this deep empathy often guides her actions.

Her role in the story is multifaceted. She begins as a spiritually aware classmate of Ichigo who awakens her own unique powers after his transformation into a Soul Reaper. She later becomes a key participant in the mission to rescue Rukia Kuchiki from the Soul Society. However, her most pivotal role is as the central figure of the Hueco Mundo arc, where she is abducted by the Arrancar to use her abilities for Sosuke Aizen's schemes. This event tests her resolve, deepens her relationship with Ichigo, and forces her to confront her own fears and strength. In the final arc, she stands as a crucial support, fighting alongside Ichigo against the Wandenreich, and the epilogue reveals she marries Ichigo, with whom she has a son named Kazui.

Her most significant relationship is with Ichigo Kurosaki. She is deeply in love with him, and her feelings become one of her greatest sources of strength. In a poignant moment, she confesses to an unconscious Ichigo that if she could live five lives, she would fall in love with the same person each time. Despite her love, she sometimes feels jealous of the close bond and understanding that Ichigo shares with Rukia Kuchiki, though she deeply respects and admires Rukia as well. Her best friend and protector is Tatsuki Arisawa, who has known her since childhood and defends her from bullies. Within the Soul Reaper ranks, she forms a close friendship with Rangiku Matsumoto, who is one of the few people who appreciates her cooking and to whom Orihime confides her romantic feelings. She also shares a unique bond with the Visored Hachigen Ushoda, who helps repair her powers and understands her abilities due to their similarities.

Orihime's notable abilities are known as the Shun Shun Rikka, or Six Flowers of the Hibiscus Shield. This power manifests from her hairpins and takes the form of six small, fairy-like spirits, each named after a flower. Her ability is fundamentally different from those of Soul Reapers or Quincies; it is the power to reject phenomena. By summoning these spirits in different combinations, she can reject and reverse events, effectively creating barriers to block attacks, healing wounds by reverting an injured body to a state before it was hurt, and even launching a direct offensive attack. The offensive spirit, Tsubaki, is the only one capable of attacking, but its effectiveness is highly dependent on Orihime's fighting spirit, which her pacifistic nature often suppresses. Her power is not absolute and has limits; it can be weakened by her own doubt or spiritual pressure much stronger than her own, and it cannot reject events that have been altered by reality-warping abilities greater than hers. Despite these limitations, her defensive and healing capabilities are extraordinarily high, considered to rival the most powerful healers in the Soul Society, and she plays a critical role in shielding Ichigo from the attacks of the god-like enemy Yhwach.