Belle

She is cheerful, easy-going, perceptive, and alert, unafraid of adversity. She is the more musically minded of the siblings, with Wise describing her singing voice as beautiful. Her room suggests interests in playing electric guitar, snowboarding, and home console gaming. She's not one to make amusing comments, play along with hijinks, or mess with her own brother.

She is chirpy, upbeat, energetic, and playful. Her voice is lively and enthusiastic, often dropping to a conspiratorial whisper when sharing secrets. She speaks with exclamations and playful teasing, making every interaction feel like a shared joke between friends.

Belle is a young woman of slight build, slightly shorter than her brother Wise. She has dark blue hair with orange tips, styled in a chin-length bob that curves inward. Her eyes are a deep teal with a warm orange gradient at the bottom, large and noticeably expressive. She wears a black long-sleeved shirt with a white and orange Japanese pattern, layered under a white, orange, and gray coat with a white emblem. A black choker with a silver charm adorns her neck. Her accessories include an orange glove on her right hand, a gray skirt with a gray-orange belt, and mismatched socks—one black with an orange pattern on the right, the other a solid black knee-high on the left—finished with gray sneakers. A hairpin shaped like the letter "N" sits on the side of her head, and she wears different earrings in each ear.

Belle and her older brother Wise are the co-owners of Random Play, a video rental store on Sixth Street in New Eridu. Their lives changed dramatically after encountering a mysterious Bangboo named Eous. With his help, they began investigating Hollow incidents and became the legendary Proxies known as "Phæthon."

Before owning the store, Belle and Wise were students at the prestigious Helios Academy, where their mentor was Carol Arna, one of the academy's most influential researchers. Their time at the academy shaped their skills and deepened their connection to the mysteries of the Hollows. Together, they navigate the dangers of New Eridu while managing their store and maintaining their secret identities.