Who is Sheen from Blue Adept and what is their importance?

Sheen is Stile's self-willed, robotic protector in Proton. Sent by an anonymous Citizen to protect Stile from an anonymous enemy, Sheen is programmed to Stile's tastes and becomes his lover. She tells him to junk her if he ever decides to forsake her as a mistress. Sheen serves as Stile's protector during his adventures in Proton and is injured several times in the line of duty.