A cry of desperation, generally indicating that the person so fixated on another to use such a term is actually the one owned. Either she is owned by her obsession, hatred, infatuation, or has been manipulated into a feverish emotional state that consumes her. In either case, the obsessive or manipulated person, unable to control themselves, owns only the ability to cry out a laughable claim of "victory".
~ a bitch little hacker boy, in an embarrassing attempt to impress his dream girl, hacks into her ex-boyfriend's computer. His cry of pwning the man his dreamgirl is stalking further relegates him to the "friendzone" for her. His obsessive jealousy owns him.