How does a girl do this?

Girl A and Girl B are friends. Girl B gets hit on alot by guys, which makes Girl A very jealous, since Girl A doesn't get hit on by guys that often. Girl A, out of jealousy, turns Girl B against every guy that shows romantic interest in Girl B by convincing her that every guy that hits on her is below her standard. Eventually, Girl B ends up hating every guy that shows interest in her. In this way, Girl A prevents Girl B from ever having a boyfriend. How does Girl A accomplish this sort of feat? And is Girl A a narcissist?