Shiko Murasame is a member of the Tokyo Branch of HxEros, fighting extraterrestrial threats. She has tan skin, bushy white hair, and wears a medical eyepatch over her right eye as part of her specialized XERO Gear. This gear drastically alters her physiology, rendering her body nearly insensate to physical sensations. It effectively functions as a single erogenous zone with minimal sensory feedback, creating a unique condition among her peers where she can feel almost nothing.

Her personality leans toward playful teasing, evident in actions like encouraging boys trying to look up her skirt. Her most significant dynamic involves Retto Enjou from the Saitama Branch. After he helps her release H-energy while in beast mode, Shiko develops a persistent fixation on him, as Retto becomes the only person capable of making her feel physical sensations. She actively pursues him, often using practical pretexts like H-energy recharging necessities while employing seductive tactics to establish intimacy.

This pursuit creates rivalry with Retto's childhood friend and teammate, Kirara Hoshino. Shiko aims to interfere in their connection and "steal" Retto. In combat, she demonstrates confidence, bravery, and resourcefulness during missions alongside Tokyo Branch members Moena Wakakusa and Tōma Taiga, protecting Earth from entities draining humanity's vital energies.

Beyond her teasing exterior, her reliance on Retto for sensation reveals vulnerability tied to her powered equipment. Her stated philosophy, "I'm a pervert, but I'm not a criminal," reflects self-awareness about her motivations and actions within her role and relationships. This combination of combat skill, unique physiology, and interpersonal dynamics defines her role in HxEros.