Neeya is a central enigmatic figure in the anime Infinite Ryvius, serving as the biological core and guardian entity of the spaceship Ryvius. She is not human but a being known as a Sphix, a living interface that controls the ship's functions. Her physical appearance—a young woman with short lilac or gray hair, red eyes, and an unusual pink outfit—is based on the body of a deceased girl named Angeles Visquez, the daughter of Conrad Vicuss, who was a key figure involved in hunting the Ryvius. Neeya first appears to the protagonist Kouji Aiba during the catastrophic collapse of the Liebe Delta space station, and she continues to appear mysteriously throughout the series, often wandering the ship's corridors regardless of environmental hazards, able to pass through solid walls and survive in the vacuum of space without protection. Her personality is initially detached and childlike; she frequently repeats back the words and thoughts of others as if trying to understand them, and she appears to be learning what it means to be human over the course of the story. Her motivations are tied to her role as the ship's protector—she awakens when the students are evacuated onto the Ryvius and gradually becomes more involved in their survival, using her connection to the vessel to aid them in critical moments. A notable relationship develops with a student named Nicks, who becomes drawn to her mysterious nature. Later in the series, she confronts Conrad Vicuss, who is shocked to see his deceased daughter's likeness acting as the Ryvius's defender. Neeya's abilities include telepathic sensing of others' emotions and intentions, interfacing directly with the Ryvius's systems, and potentially manipulating the ship's environment. Her development is marked by increasing empathy and understanding, culminating in her decisive interventions that help the stranded crew survive their ordeal. Ultimately, Neeya is a non-human consciousness that bridges the organic and mechanical, acting as both a catalyst for the story's mysteries and a key element in the resolution of the students' struggle.