Chinatsu Furuhashi is a 21-year-old university student, making her the senior of fellow student Ryuichi Moroboshi. She possesses violet hair, often styled with spiky bangs in a ponytail or shoulder-length, and garnet-colored eyes. Her slim, pale figure stands 172 cm tall with measurements of 89-59-90 cm (bust-waist-hips). Her typical wardrobe includes casual pieces like tank tops, jeans, miniskirts, and occasionally bikinis, often accessorized with a choker. Personality-wise, Chinatsu presents as carefree, lazy, and mischievous, frequently using the pronoun "atashi." She exhibits a tomboyish and friendly nature, engaging in teasing behavior, particularly directed at Ryuichi. Her interactions are characterized by aggressive or forward moves on him without hesitation, reflecting her comfort with assertive advances. She sometimes playfully addresses him as "shonen" or "good boy," suggesting a mix of playful dominance and underlying care in their dynamic. Chinatsu serves as both Ryuichi's roommate and senpai within the boarding house where they reside. She lives there alongside Ryuichi's stepmother, Kyōko Moroboshi, and several other women after Ryuichi moves in following the destruction of his apartment. Chinatsu participates in the group's treatment of Ryuichi as a "sex toy," with her role emphasizing her teasing and sexually proactive approach towards him. Her character remains focused on these interactions within the household's harem dynamic across the OVA episodes.