Harold in the mean time had driven Karen home to her apartment. They went in and sat down on the couch. Neither had said anything on the trip back. Harold and Karen had been seeing each other for over three years now. They had started out innocently enough, Harold was upstate on business and he and Karen had gone to dinner. Susan had known about that, what she did not know was that they had too much to drink at dinner. When the cab dropped them off at Karen's apartment she asked Harold up for coffee. Harold put on some music while Karen made coffee and while the coffee was brewing they started to dance. During the dance Karen looked at Harold and he kissed her. Karen had broken up with her husband a few months before and had been alone since. She responded to Harold's kiss and started dancing real close to Harold. They danced so close that Karen could feel Harold's cock starting to get hard. She started to rub her crotch up against his while they danced. Harold unzipped her dress and pushed it off her shoulders letting it fall to the floor. He started kissing her neck and worked his way down to her smallish but well formed breasts. He removed her bra and licked her stiffening nipples. All pretense at dancing gone now. Karen had started unbuttoning Harold's shirt and pulled it off she undid his belt and opened his pants she let them fall to the floor and pulled down his shorts letting his cock spring free. Karen could not believe the size of his cock, she had always thought Susan had been exaggerating the few times that she had talked to her about their marriage and problems. Karen reached down and grasped his swollen manhood in her hands. Harold stopped nibbling on her breasts when she grabbed him. Karen sank to her knees in front of Harold and slid his huge cock into her mouth. Harold was shocked, Susan would never think of doing that. The one time he tried she had not spoken to him for a week. Karen had a natural desire to suck cock and Harold could tell that she enjoyed it. He knew that he would not be able to hold off shooting his load for long. He had not fucked Susan for several weeks now so he had a large load to shoot. Karen seemed to sense this and sucked harder and faster. Harold tried to warn her he was about to shoot his wad but Karen did not seem to care. Harold ex-ploded right there in his sister In laws mouth. He was amazed that she was not mad, she eagerly swallowed every drop of cum that she could suck from his cock. She let his cock slide out of her mouth and stood up. Taking his hand she led him to the bedroom. Pushing him down on the bed she took his now limp cock in her mouth and started working it with her lips and tongue and lips. Harold could feel it starting to get hard again. Harold grabber Karen by her slender hips and pulled her pussy over his face. Karen dropped her steaming hole on Harold's face and he started sucking her cunt as she sucked his cock. Working his tongue over her clit, he drove Ka-ren wild. He had to hold her hips still so she would not bounce off his face. When Harold slid his tongue deep in Karen's pussy she came with a force long pent up in her. Her juice was running down the side of Harold's face as her whole being quivered and shook. Karen just laid down on Harold's body not moving. Harold rolled her over on he back and crawled between her wide spread legs. Looking at her exhausted form he grinned and said "we are not through yet" he moved his swollen cock to the entrance of Karen's wet pussy and pulled her onto his shaft. Karen felt as if she was being split in half by Harold's cock. She had never had a cock of that size in her pussy. He was definitely filling her up. When Harold felt his cock hit bottom he pulled Karen's leg up on his shoulders and pulled his cock almost out of her hot pussy and slowly worked it back in wanting her body to adjust to his size. Karen moaned and worked her hips against him. "Please go faster" she moaned "harder harder." Harold was glad to comply and started pounding his cock into her hot tight pussy. Karen closed her eyes and just rode with her feelings. She could feel her pussy starting to quake with the pounding her clit was taking from Harold's huge cock. She arched her back as her muscles tightened and released in the largest orgasm she had ever had. Her pussy clamped on Harold's shaft as he exploded his load into her hot flowing hole, his cum mixing with her juices. They both collapsed on the bed their passion spent. Harold woke up in the morning and had to stop and think about where he was. The room did not look anything like his hotel room. He looked over and saw Karen next to him and the memories of the night before came racing back. Karen rolled over and the sheet fell off her. Harold studied her sleeping form on the bed. Her breasts were firm and stood proudly even though Karen was laying on her back. Her body was slim and trim. She was a contrast to her sister who had a lush big breasted body. Susan was well built but not in any way fat. Her breasts were as firm as a set of tits that size could be. She was also very repressed sexually. Harold longed for variety, wanting Susan to show some interest, or to take charge of their lovemaking. Susan had never sucked his cock like Karen had. If he had come in Susan's mouth like he had with Karen the night before she would have killed him, not sucked him dry. Harold felt bad that he had slept with Karen, but he told himself that he had deserved a break. Karen woke up and slid her hand between Harold's legs and grasped his cock & balls in her warm hand and Harold felt an immediate response. He tried to say something but Karen stuck one of her firm tits into his mouth stopping what he was trying to say. Stroking Harold's cock to its full length Karen shifted her pussy over it and put its big red head into the tight entrance to her cunt. She slowly worked his big cock into her tight hot hole and started rocking on it. Sitting straight up she moved upward on the shaft until only its head was still in her pussy. Karen stayed in this position for a second and then dropped straight down ramming it to the hilt into her cunt. She started rocking faster and faster on his huge shaft until letting out a scream she shuddered and jerked impaled on the shaft that gave her all the pleasure. Slowly Karen started rocking again working the shaft with her hot velvety hole until Harold unable to hold back any longer exploded into hot cunt. As Karen sat on Harold's slowly shrinking shaft she looked at him. "I have wanted to have you in my bed for years. I always loved you from the first time Susan brought you home. I knew that she could never make you happy the way you deserved. Harold had no idea what to say but Karen continued. "I know that you will never leave Susan, but I will always be here for you." And Harold had to admit that she always had been. He had not planned to continue seeing Karen, but he could not stay away. He loved his wife, but he loved her sister also. Their time together was always special, and always different. Their sex life never got boring or dull. They always managed to find time together and for three years things had been perfect until now. Coming back to the present Harold looked at Karen. She had been sitting there watching him and he was not aware of it until now. "What will you do now?" she asked. She was hoping that he would move in with her as she had always wanted. "You know that Susan will never forgive either one of us for what has happened." Harold looked at her and said "I will pack my clothes and hope she can be convinced to be reasonable, this has been coming for a long time." "Would it be o k if I stayed with you for awhile?" Karen smiled and walked over to Harold "you can stay here the rest of our lives if you want I love you." Karen kissed Harold and told him he better go get his clothes before Susan and Michael came back to the house.