Harry was secretly relieved when Ginny stopped. He figured she would think it was gross when he climaxed so it was better that they didn't get that far. Girls thought that, right?
He figured eventually they did get over it to let it happen but they weren't there yet. Harry really had no idea. Cho had never let him finish when they actually touched.
Concentrating, he explored Ginny's folds through her knickers. She felt so amazing. Harry's middle finger found the tiny bundle of nerves atop her slit and lightly teased it with his finger.