Zak smiled, already knowing what he wanted, he teased her slit a bit more, his fingers diving in deeper as he worked her ass still a bit more. His length was throbbing for attention now, and he was getting a tad impatient himself. He grasped her hips, softly teasing her slit with the tip of his swollen length before he began to softly push into it. This was not his choice, but a little extra lube never hurt anyone now did it. 'Mmm..y..your so tight sis," he said, slipping in and out of her tight hole feeling his length being grabbed by her inner walls.