He knew if she continued he wouldn't last, and he wanted to make her come one more time, wanted to see her shake and cry out. He loved the sight of her when she lost control that way. Reaching under her he found her nipples and began to twist and pull at them.
"Oh God, Bill, I'm going baby, yes, yes!"
That was the signal he had waited for, she was going wild now undulating on him fiercely, as she cried out over and over again. He fucked into her like a wild man, pumping deeply into her sex as he continued to twist and pull her hard nipples.
Then his seed rose in him rapidly, traversing his member, scorching the underside of his cock as the thick liquid fire rushed to its exit. Blast after blast of the thick hot fluid slammed into her cervix, filling her organ to overflowing with the warm liquid as she lay beneath him whimpering in ecstasy.
Her mind exploded outward into a thousand tiny fragments, then into darkness. It contracted just as quickly to a small single point in front of her. She drifted in a sea of blue white fire, its flames licking at her body, caressing her, cooling her mind and her flesh. She slowly descended back into her body sated and radiant, but with her energy somewhat depleted.
"My God, Bill, that was the best," she told him.
They lay on their sides when they were finished, facing each other. They were completely satisfied with each other's performance and vitality. Exhausted, but sated and wonderfully satisfied.
They kissed. They went after each other's mouths like two horny teenagers. She asked him to spend the night there with her, and he accepted her hospitality with enthusiasm.
They spent the weekend together, locked away in a world of their own making. They spent the time exploring the wonders of each other and becoming acquainted in a new kind of relationship.
William's mother marveled at the new level of genuine interest in her sister's welfare that Bill displayed after that weekend. He began stopping by her home several times a week, calling her to see if she needed anything and generally looking after her. He was such a good boy.
His affair with Lisa never really ended. When he left for college her house was always his first stop when he returned home. Even later when his children came, he was still looking after her welfare. Not as often of course, but at least on a continual ongoing bases.
She always remained, and would always be, his favorite aunt!