I was in ninth grade when it happened. I think it was inevitable, not that I knew that before it happened. It was only after that I came to see the patterns.
Karen was a year younger than I and in eighth grade. She was a walking wet dream, even for me, and I was just at that age when I could cum in a second, then a third, then a fourth etc.
We had a different relationship than most brother sister tandems. We didn't argue and didn't put each other down. Oh, we teased each other, especially at cards, but it was never the spitefulness of many siblings. I guess it was because of her. Karen was a peaceable soul and loved her big brother, me. She had Dad wrapped around her little finger, whereas I couldn't do anything right. Freud would have had lots to say about our family, the way he loved her, and saw me as a challenger.
Anyway, Dad wouldn't punish her but he would take the belt to me in a flash. When Karen was about four and Dad was wailing away on me with his belt, she jumped between us and he accidentally hit Karen leaving big red welts on her arms and back. That I was already covered with welts got no sympathy, but Karen with one, well Dad fell on his knees and begged forgiveness, of her. She put her arms around me and cried. Somehow, that broke him and he never took a hand to me again. Oh I got punished, but never whipped again. Karen was my hero. I would do anything for her. She never took advantage of me either.
Our house was kind of unusual. Karen and I shared a bedroom when young. The bedroom originally had a door to the backyard. So when the folks decided we should each have our own bedroom, we were both getting to be ten or so, they just added a room behind mine and changed that outside door to an inside door. That meant that Karen had to go through my room to get to hers. Since we had been sharing a room till then, it wasn't a big deal. But as I hit puberty and became body conscious, it did start to matter, to me. Of course, Karen walked in on me naked more than once. She never acted like it was a big deal. She ignored it on the surface. She also caught me jacking off a couple times and tried to act like it wasn't a big deal. But maybe the second time she couldn't help but ask what I was doing. That led to a very embarrassed explanation from me. She got fascinated and after admitting that her friends had told her about it, for girls, I got fascinated. That was some eye opening talk we had. I guess we were also unusual in the openness we had in talking, also because of Karen.
I think it was right about then that we were talking one night and I complained that she would walk in on me naked but she never walked through my room naked and always kept the door closed to her room. She got serious and asked if I was really bothered by that. I said yes. But then felt a little guilty, like I was perving on my sister. That night, after she came back through my room to hers after her bath, I noticed she didn't close the door between our rooms. I lay on the bed for a while, staring, and kept wondering, did she do that on purpose? Finally I couldn't stand it and slowly and silently, went over to the door and peeked around. There she was lying on her bed naked. My Lord, she was stunning. I loved her, as a sister: that was really the first time I appreciated her as a woman, for she had become a woman. She looked up and saw me peeking. She smiled and went back to reading her book. How she could be so nonchalant, I don't know. But after that, neither of us was all that body conscious. I sure couldn't be when she seemed to make it no big deal. No way was she going to be more mature than I. Darn right. Yeah, darn right that she trained me just the way she wanted me and I never knew it.
Like I said, it was during her eighth grade year that it happened. She was having a sleep over. It was driving me crazy, all those girls in her room giggling like crazy. Worse, I knew they were all in almost nothing. I had several peeks of one of the girls in just panties and a tight top. If I didn't know better, I would have thought they were doing it on purpose, driving me crazy! Hmmm.
Mom came through my room and into Karen's. "Okay girls, it's time for bed. I don't want to hear any more noise."
I heard the girls all calling out, "Goodnight, Mrs. O'Hara." Mom flipped off the light and shut the door. On the way out of my room, she said, "Go to sleep, and leave the girls alone."
I started to protest but she turned out the light and shut the door. Guilty and I hadn't even done anything!
It was quiet for maybe ten minutes, then the door between our rooms opened, "Has she gone to bed?" sis asked.
I listened at the door, "I think so."
"Good, put the light under the blankets," Karen said back into her room. "Want to join us?" she asked me. "We're going to play truth or dare."
"Okay," I said trying to hide my enthusiasm.
I followed Karen back into her room. The girls had strung a large blanket between her bed and the dresser. It blocked the lamp light from hitting her window. But under the blanket it was bright. The girls were sitting in as semi-circle. I couldn't help it ... seeing them all in panties and tight tops and popped a boner. Since all I was wearing was pjs, it was apparent as all get out. Karen noticed and grabbed my hand as I tried to back out of her room. She pulled me under the blanket with her friends several of whom I could tell were looking at my boner.
"First two losses mean a piece of clothing," Karen said. I realized that everyone had two pieces of clothing. I had my pjs and each girl was only wearing panties and a top. God, in two rounds I could be naked with four naked girls. My boner got even harder.
"After that a loss means a penalty," she finished. "Who goes first?"
"I will," Paige said. She turned to me and asked, "Who's prettiest here?"
Great, my first question and I'm given the type of question that kicked off the Trojan War. I could answer that question honestly and still be okay. "Honestly, I think all four of you are equally pretty, including Karen."
Paige came back with, "No fair. You didn't answer the question. Take it off."
Karen spoke up, "I know Mike. He answered truthfully. I can tell when he's lying." Leah and Makenzie nodded in agreement. Paige looked nervous. Karen smiled devilishly, "We all agree. You lose. Take it off."
Paige looked over at me as I watched amazed that I was about to see her tits. "He's staring."
Leah laughed, "We're all staring. Take it off."
Paige looked around once hoping for support. But I could see this was a bloodthirsty group and there would be no mercy. She lifted her tight top and tossed it behind. I tried not to stare but damn she looked cute with her tits sticking out like that. There weren't really big, but still, they were only the second set of boobs I had seen in the flesh. Her pale skin was deliciously in contrast with her long dark black hair that flowed down over her shoulders.
The questions went around quickly with everyone losing until we were all naked. Then there was the first penalty question. I lost and Makenzie held the penalty choice. "I want to watch you do it," she said. The other girls giggled but agreed with, "Yeahs."
I looked at Karen not quite knowing what she meant, do it. Karen saw my uncertainty and said, "Jerk off." It was obvious that they had been talking earlier since they all knew what it meant.
"No way," I protested.
"Don't be a stick in the mud. Do it," she said.
Eight eyes were avidly watching, including Karen. I knew I couldn't back out. I lay back and started slowly stroking my cock. They gathered round. As my hand slid up and down I felt their legs touching me as they slid in close. Feeling them naked and so close nearly drove me to cum.
"Can I do it?" Makenzie asked.
"Huh?" I was surprised.
"Can I?" she asked.
Karen answered for me, "Sure, go ahead."
Makenzie looked at Karen and smiled as she realized Karen and the girls had me right where they wanted. Her hand wrapped around my shaft as I let go and started stroking my cock. "So hard," she said almost under her breath.
Karen knew how I liked it done, having watched me more than once, "Faster," she said to Makenzie. She sped up and I found myself almost ready to cum right then. The erotic energy with four girls watching was more than I could have ever felt. The rumblings began and bang I exploded like never before. I saw the first glob of cum fly high in the air as the girls all gasped. Makenzie didn't stop and one after another four or six globs of cum went flying up into the air until I was dry. Makenzie dropped my cock which was already subsiding a she stared at her hand covered with gooey cum.
Karen had a towel handy, like wasn't that a coincidence, and gave it to Makenzie who cleaned up her hand before handing me the towel. I cleaned up as the girls all stared. As I sat up they continued the game. Leah lost the next question on a disputed answer. Karen smiled as she gave Leah her penalty. "You have to let Mike lick your kitty." Leah blushed furiously as the other girls giggled. The girls didn't seem surprised by the penalty and later I realized this had all been talked about beforehand. "Do it," Paige said to me.
.... There is more of this story ...