Sharon Kiveat (played by Karen Witter) was a special education teacher. When Mulder and Scully began investigating the bizarre lightning-related deaths that would later be attributed to Darren Peter Oswald, they met Kiveat.One of her students was Oswald, who was so infatuated with his teacher that claimed to have fallen in love with her. Oswald was very jealous of Kiveat's husband (and his own boss) and caused a traffic light to change, resulting in a serious car accident. Oswald made a show of reviving him with his electrical powers when he caused the defribrilators to fail.
After killing Bart Liquori, Kiveat tried to appease Oswald by willingly going with him; Oswald greatly wanted to marry her but had no plans beyond that. When confronted by several FBI agents, Kiveat ran away from Oswald, leaving him forever. While Oswald searched for Kiveat, Mulder and Kiveat observed Oswald being struck and incapacitated by lightning summoned from his uncontrollable frustration. After Oswald was taken into custody, Kiveat and her husband were safe and sound. (TXF: "D.P.O.")