Reika appears as Yuna's classmate in the anime's third season. Hailing from wealth, she presents herself as a beautiful and elegant young lady, taking evident pride in her appearance. Her strong admiration for Takumi, a popular soccer player introduced that season, drives much of her behavior. This admiration fuels jealousy toward Yuna due to Yuna's positive rapport with Takumi, prompting Reika to mockingly call Yuna "scrub head."

Others find her personality unpleasant, though not truly evil. She typically surrounds herself with followers whom she commands. Reika harbors a distinct fondness for telling puns, but these jokes rarely land; only her entourage laughs, often out of obligation rather than genuine amusement.

A key vulnerability is her pronounced fear of ghosts and supernatural phenomena. This fear is exploited when an alien entity possesses her body in Episode 69. Later, in Episode 72, she encounters Yuna transformed into a puppy. Unaware of the puppy's true identity, Reika is charmed by its cuteness, adopts it as a pet named "Angela," and dresses it in fashionable dog clothes. Despite her usual self-centeredness, this situation reveals an unexpected capacity for tenderness and responsibility, as she actively works to rescue the puppy after it is kidnapped.

Within the narrative, primarily set in Okinawa New Town, Reika functions as a rival to Yuna, creating friction.