Stroking the Crossbar
when making love to a woman of a slighter build, it can be felt that the normal padding a woman has around her vagina is not present. In fact, in the case of very slight women one can feel a bone perdendicular to the penis that creates some discomfort known as the 'crossbar'. Stroking the Crossbar is simply having sex with a woman with a bony vagina.
Stephen had enjoyed his sex the night before but was feeling a little damaged from "Stroking the Crossbar".