Shay Heath, of Manchester, N.H., has a tattoo showing a spider's web with two hearts on it just above her skate. Following the nationwide resurgence of the crash-and-slam sport over the past three or four years, a group of 20- and 30-something women began rallying at Tyngsborough's Roller Kingdom every week from all over the Merrimack Valley and southern New Hampshire to skate, vamp, and train for on-rink battle.