Stella Korabelishchikov is a doctor aboard the spaceship *Beautiful Sophia*, working alongside Kenzo Hyoudo. She has short brown hair, purple eyes, and always wears half-rimmed red glasses. Her standard outfit is a blue sweater and skirt under a white lab coat, though she sometimes switches to a green and red uniform with a matching hat.

Professionally, Stella exhibits a tendency to view individuals as subjects for scientific analysis, often adopting a somewhat sadistic approach. She treats Kenzo as a professional rival, resulting in enthusiastic yet antagonistic interactions.

As a key researcher, Stella informs Dan Bashin about the imminent Earth reset triggered by the emergence of the mazoku continent Oct. Her study of the Otherworld Observation Records identifies the 12 Zodiac X-rares as essential tools to prevent catastrophe. After Barone is injured by Duc, Stella volunteers to study the mazoku. Her DNA analysis reveals humans and mazoku share identical genetic structures, establishing them as the same species.

Stella joins a critical mission to locate the polar shrine necessary for activating the 12 Zodiac X-rares. Traveling to a space station, she helps discover the shrine's location and encounters Angers Loche, an astronaut preserved in cryogenic sleep who possesses one of the X-rares. Returning to Earth, she promptly reunites with Kenzo to proceed to the pole. There, they use the Otherworld Observation Records to unveil the shrine, recognizing the necessity for an individual to activate the X-rares by pulling a trigger.

During the final conflict, Stella monitors the energy accumulation from the 12 Zodiac X-rares alongside Kenzo and Angers. In the epilogue, she bids farewell to Kenzo, facilitating his return to his original time period with Mai Shinomiya and Hideto Suzuri.