A Massachusetts woman accused of posing as a teenage boy to prey on a West Virginia girl pleaded guilty to one federal charge Wednesday and could face up to 30 years in prison when sentenced. Carissa Hads, 25, of Quincy, could also be fined as much as $250,000 when sentenced on the single count of traveling across state lines with the intention of having sex with a minor. She is in custody and appeared before US Magistrate John Kaull in Clarksburg to enter her plea. Investigators said Hads pretended to be an 18-year-old named James Puryear Wilson.