Kirsten von Greiner took several minutes to freshen up for the birthday dinner her parents held for her and her twin brother, Karl. This frustrated him, as he was eager to get to Maureen's and not making everyone wait for them. He especially disliked delaying his older half-brother, Trevor. There was more than a little hero worship involved there, since Trevor was a deputy sheriff and already had some recognition for his work on the force. The last thing that Karl wanted to be was a nuisance to his big brother, who was nice enough to agree to drive them to the restaurant for the dinner in their honor. Why exactly Kirsten had asked to stay behind and then spent so much time primping was beyond Karl. It made no sense at all to him.

"Sis, Trevor's waiting on us! What's taking so damn long?" Karl hammered impatiently on the bathroom door. That was when he heard laughing behind him.

"Bro, you have some learning to do about girls. If a little time in front of the mirror is the worst thing that you face, you're a lucky man. Some of us have it a lot worse than that," Trevor stood behind him.

"Well, I just felt bad because you're waiting for us, to take us to Maureen's. That and the whole family is likely to be there by now. It's embarrassing," Karl griped.

"Karl, did it ever occur to you to ask why your sister wanted you to stay behind with us?" Trevor asked his adolescent sibling.

"Not really. I just assumed that she wanted to mess with my head," Karl shrugged.

"Yep, you have some learning ahead of you. Our sister is primping for you, Karl. She wants to impress you first, ahead of anyone else. She wants you to approve, so she'll feel confident in showing off for everyone else. If you don't like how she looks, she'll just start all over again. Your opinion matters that much to her, so that she'll make everyone wait, just because she trusts you that much. I'd say that there she's trying to send you a message, and if I were you, I'd listen good and hard, instead of complaining," Trevor grinned knowingly.

"What message?" Karl scratched his head, having stopped knocking on the door.

"I think that you'll find out pretty damned soon, if you care enough to pay attention to the signals. Something tells me that doing so will be worth the time and effort. Relax, bro. Our sister has a plan, and I think that it's likely to be good news for you, at least. Don't be a jackass and blow it. Do you hear me?" Trevor urged his brother.

Karl suddenly had a mental image and blushed. Then he really felt bad, because his thoughts weren't very brotherly. That couldn't be what his twin sister had in mind, could it? He would love it to be, but he didn't trust to his luck. He was too young to know enough about that. He then just decided to shut up and listen to his brother's advice. Whatever came of this dinner, his sister had something special in mind for him, and that was better than a negative surprise. Half of the guys his age couldn't stand their sisters. He was fortunate that way, if not as lucky as he wished. Trevor was married, so he knew a lot about women. Unless he was part of a prank, Karl should take his counsel.

"Alright, bro. I'll do as you ask," Karl started to shake hands with Trevor, but the firstborn hugged him instead.

"More advice. Don't be afraid to hug family. It doesn't make you gay, though there's nothing wrong with that," Trevor told his little brother.

"Well, obviously, Trevor. Grandpa's gay. I wouldn't call him any less of a man for that. Him or Uncle Earl. It's just that I didn't know how you would feel about it," Karl stammered.

"In case you haven't noticed, our family isn't normal. That includes our attitudes about showing affection. You hug your dad all of the time, right? You hug Grandpa and Uncle Earl, too. It's okay to hug a guy, if you care about him and he doesn't mind. I hug my father, too. You used to hug me a lot, when we were younger. Just because we're older doesn't mean that we have to stop hugging," Trevor reassured him.

Just then, Kirsten finished and walked out of the bathroom, stunning the menfolk in her sundress and heels. Why she wore something quite so formal to a "sweet sixteen" birthday party at a bar and grill puzzled Karl, though Trevor's smile indicated that he caught on immediately. The older brother even winked at Kirsten, who went red in the face when she realized that Trevor was onto her. Karl gestured to Trevor, trying to get a hint, but his half-brother just shook his head, as if to say, "Forget trying to find out until she's good and ready. She'll tell you in her own time."

"Okay, let's go," Trevor simply told the twins.

They were both eager to leave, though their motives were quite distinct. It turned out that some of Karl's worries were valid, since the entire Von Greiner tribe awaited them at Maureen's. Then again, since this was a party in their honor, they could be forgiven for being "fashionably late". That didn't mean that no one teased any of them. Grandpa and Uncle Earl took particular delight in cracking some jokes at their expense. Since Grandpa was known for his sense of humor, no one thought this to be strange or mean. He loved his grandchildren deeply, but felt that anyone should be able to cope with some wisecracks and good-natured teasing. Besides, he was visibly ailing and needed something to lighten his mood from thoughts of his terminal illness.

Karl wasn't worried anyway about the jokes or witticisms that Grandpa and the others made. Kirsten easily gained much of his attention during the night, though he certainly appreciated the other girls present. The way that she acted toward Karl didn't exactly discourage him. Far from basking in the royal treatment that she received as the birthday girl, Kirsten simply thanked the givers for each gift and turned her eyes back on her twin. She didn't waste an opportunity to flatter him or shower him with affection.

When Kirsten's turn to make her birthday wish came, she was as silent as ever, but her facial expression was louder than a trumpet. She blew out the candles and then blew a kiss directly at Karl, her eyes fierce with the intensity of her apparent needs. She also took every opportunity to turn his head and make him nice and hard. Everything from finding excuses to walk across the restaurant and let Karl see the shape of her ass and legs to touching his arm on some pretext or another had the effect that Kirsten desired.

By the time that the family got home, Karl was desperate to get alone and jack off. Kirsten had seriously excited him, and she seemed to have done so on purpose. Dad followed him and knocked on the door, just before Karl could start playing with himself. Karl quickly pulled up his pants, but Dad had a look on his face when he entered the room that made it apparent that he wasn't fooled.

"Karl, you were about to masturbate, weren't you? There's nothing wrong with doing it. I just want you to level with me as to why you're so excited. It's because Kirsten kept flirting and teasing you. I'm sure of it. Again, I don't blame you. She's made it apparent that she wants to sleep with you. I don't think for a second that your sister would do all of that, just to leave you frustrated. She went out of her way to look good for you, after all. I saw her face when she made her birthday wish, too.

"Well, Karl, since the two of you have feelings of some kind for each other, I want to say a couple of things to you. You know that your mother and I don't have a monogamous marriage. We're also married to both Aunt Haley and Aunt Michelle. The laws have thankfully changed to allow this. You've also seen that Trevor's dad has two wives of his own, who are married to each other as well. You know that Grandpa is married to Uncle Earl, too. This isn't a conventional family. Uncle Ryan and Aunt Stephanie are man and wife as well as brother and sister. Uncle Red lives an unorthodox lifestyle as well.

"What I mean to say is that if you want to date your sister, you have my blessing. Just don't be mean to her. No beatings. No black eyes. If you want to break up with her at some point, do it like a man and make it clear that you still love her as a sister. If she decides to break up with you, remember that she still loves you as a brother and don't go all crazy about it. Don't stalk or harass her.

"If you want to have an open relationship, tell her upfront. If you want to be exclusive, make that clear instead. If you two agree, then that's good. If not, you'll probably have to go back to just being brother and sister, as hard as that is. We're not going to judge a consensual relationship of any kind between you. Your mother and I will understand, either way. I, for one, feel more comfortable with you as your sister's lover than many other men. I know that you'll be good to her. I still have to say these things for the record, to cover all bases.

"So, Karl, are you going to grant your sister's birthday wish or not? Are you going to sleep with her? If so, then we can arrange for you guys to share a bedroom. If not, well, there's no accounting for taste. I think that I already know the answer. Just say the word and I'll bring her in here so we can talk freely about this," Dad declared to his eldest son.

"Dad, I want Kirsten badly. I hoped that you'd understand, but I was still a little worried. I also wanted to be sure that I wasn't misreading her intentions. She seem to be interested, but I didn't dare to ask her yet, in case I was wrong. I guess that I'm not just imagining things. Please call her in so we can talk. I want to tell her how I feel about her," Karl answered, as flustered as he was.

"Alright, I'll get her for you. Congratulations, son. You have the love of a very good young woman. I hope that this works out for both of you," Dad smiled broadly and hugged Karl, before leaving Karl's bedroom to find Kirsten.

Kirsten entered the room a few minutes later, looking nervous and a little embarrassed at the fact that she had been so obvious in her affections. Even so, she realized that her efforts were about to be rewarded. Her twin brother apparently shared her feelings and had even told Dad so. The awkward, but hopeful grin on Karl's face told her what she needed to know. Karl loved her as more than just a twin. She would get her birthday wish, after all.

"I think that you kids and I need to talk a little. Kirsten, I told Karl that I'm fine with you two dating and even sharing a room. However, we need to be clear as to what kind of relationship you guys want. Do you want to be exclusive or open? Do you want to even add others later? Tell me and each other, right here and now. Your mother already knows that I'm having this talk with both of you. She's relieved that I'm doing this, since she is naturally more timid than I am. Let's discuss this frankly. You're not quite adults, but close enough to have a grown-up discussion and a mature relationship," Dad insisted.

"Yes, for the record, Karl, I'm in love with you. Dad, I want Karl on any terms that he sets, but I'd rather have us join your cozy little circle. It's already more or less limited these days to friends and family. There's no reason why we can't participate. That includes Bridget, Natalie, and Trevor, if the circumstances are right. That's up to them, I know, but I like the idea, at least. Basically, I just want to 'keep it in the family', as the saying goes.

"Think about it, please. No STDs. No outrageous demands and pressure for 'fidelity' from people who don't understand us. It takes a few generations of consistent inbreeding for any serious genetic problems to occur, and quite a few members of our 'family' are not blood relations, anyway. Can't we be lovers, all of us? I know that it sounds radical, but you asked me what I want," Kirsten stunned her father and brother with her true feelings.

"Well, Kirsten, I think that's clear that I love you the same way by now. Hey, Dad, it makes sense to me. I'm not exactly a one-woman man. She's right that you guys basically stick to a few trusted partners these days. That's smart, since it gives you variety balanced by safety. I'm in favor of her plan, though it's up to you. However, I'm curious as to why she left Cassie and Hector off her list. Did you mean to omit them, Sis? And Trevor's married to Jamie, who doesn't strike me as the 'swinger' type. Do you expect them to break up, or something? Those are just some questions that I have," Karl confronted his sister, wanting to hurry up and resolve this, so he could fuck her at last.

"It wasn't an accidental omission, dear brother. Cassie and Hector are a little younger and I'm not sure what the future holds for them. They seem rather close and sometimes even possessive of each other. I think that they might become an exclusive couple someday soon. I hope that I'm wrong, but I'm not ready to count on including them. Of course, Dad has that 'special power' of his, but he wouldn't abuse it.