Cruise Doubledate with My Sister

"Fine. You come up with the details for the horseback riding and teach it to me later. Moving on. I think we're going to have to fudge how Jacob and I broke up. I think we need to imply that it happened later in the week. Let's say that he constantly antagonized Thomas and that was the final straw for me. Okay so far?"

"Yes," Rebecca and I said.

"Wrapping up. Saturday night, I sat you two down and knocked some sense into you. Rebecca, you agreed to move in with Thomas. Thomas, you agreed to...Thomas, you have to agree to something. You're getting back together won't make sense unless you give Rebecca something."

"I agreed to go to church with her every Sunday if we can find a church that we both like."

Rebecca's eyes went wide. "Thomas, you would do that for me?"

"Yes. I've been kicking myself since Monday for not proposing that months ago."

"Oh, Thomas! I love you!" Rebecca showered my face with little kisses.

"You two can continue that in a little bit," said Caitlin with a smile. "Let's finish up now. Thomas agreed to go to church with Rebecca if you can find a church you both like. Rebecca agreed to move in with Thomas. You kissed and made up. That I was in the room when you made love is one of those things to never be mentioned again. Any questions?"

Rebecca and I said nothing.

"We'll run through it again when I get back. I'll go look for Jacob. I'll tell him that you two are back together. I'll get your stuff out of his cabin so you don't have to deal with that sleazeball again. I'll tell him that if a whisper gets back to any of Rebecca's friends that something happened between him and Rebecca on this cruise, I'll kick his ass up and down the street in front of his damn truck stop." Caitlin gave us a smile that left no doubt that she would enjoy doing that. "Okay, I'm off. I'll be gone long enough for you two to make love again. There's nothing like a slow morning fuck."

Rebecca opened and shut her mouth several times. "I'm not ready..."

Caitlin gave her a "haven't you learned anything" look.

Rebecca moved her hand in front of herself like she was wiping out her last statement. "Look, you told me last night that I need to do whatever it takes to keep Thomas happy. You told me that I need to up my game in bed. I agree, but I don't know anything about sex. The tips you gave me last night were helpful, but aren't nearly enough."

Rebecca stopped there. I expected her to continue. I looked at Caitlin and she had a confused look on her face.

"And so?" asked Caitlin.

"And so, I want an in-depth sex lesson. Something more than the tips you can give while watching Thomas and me."

Again, Caitlin looked as confused as I felt. "And that would be?" asked Caitlin.

"That would be that you and Thomas make love while I watch and you explain to me what you're doing and why."

I was floored.

"You want me to make love to Thomas in front of you?"

"Yes. I know it sounds crazy. Before I came back, you were going to make love this morning then go back to being a normal brother and sister. I'm asking you to stick to that plan. I'm not ready to make love and you are. It will make Thomas happy and I'll learn how to keep him happy. So many things have happened on this cruise that I'll never discuss with anyone, what's one more?"

Caitlin looked at me, then back at Rebecca, then back at me. She was as stunned by Rebecca's idea as I was. "Thomas, what do you think?"

"I've had a great time with you, but I know it has to end. I think it would be a nice way to end it."

"It would be a nice way to end it. I'm game."

Caitlin emptied her pockets, quickly stripped, climbed on the bed and pulled the covers down. "Anything in particular you want to see?" she asked Rebecca.

"Different positions. Ideas for more variety. Whatever will make it better for Thomas."

"And better for you. The more you enjoy sex, the more Thomas will enjoy having sex with you." As Caitlin flopped on her back, I got on one side of the bed as Rebecca got on the other. "Do you mind if Thomas and I kiss?"

"No. Act like I didn't come back last night. Make it the best you can for Thomas."

"You continue to amaze me, Rebecca." Caitlin turned to me. "Are you ready to give her a good show?" Caitlin pulled me down for a kiss. "You're going to have to rev me up. I was steeling myself to confront Jacob and I'm not in the mood for sex yet."

I kissed Caitlin repeatedly as I rubbed my hands all over her body. "You have such a beautiful body, Caitlin. I'm going to miss it."

"I'm going to miss you, Thomas. You're a great lover."

I kissed her hard, then slid my tongue into her mouth. Our tongues battled for a little while. I stopped roaming with my hand and instead concentrated on her tits. Her nipples were hard between my fingers as I played with them. She was definitely getting revved up. I slid my hand down from her tits then back and forth across her rib cage and stomach. When my hand reached her small line of crotch hair, Caitlin raised her crotch to meet it while fucking my mouth with her tongue.

Caitlin let me make a few circles around her clit, then pushed me back and turned towards Rebecca. "You like sexy games. Here's one. Thomas, get between my legs." I moved into the missionary position. "Now slide a little further down until the bottom of your stomach is where my clit is. Good. Now rub your body against mine in a fucking motion."

I pressed my lower stomach against Caitlin's crotch, then slid upwards using the same motion as fucking in the missionary position. Caitlin lifted and pressed her crotch against me as I slid up. When I moved back to my starting position, Caitlin dropped her crotch back down.

"That's it, Thomas. Lots of pressure against my clit. That feels so good."

As I slid upwards, my hard cock made a beeline for her pussy. I needed to slide only a little more forward and I would be in. A long steady stroke, then back to our starting position. A long steady stroke, then back to our starting position. Being so close to fucking but stopping short made this game very exciting. Is this how we were going to start fucking?

"That's enough, Thomas. Come back up here and finger me."

I got on the bed to the right of Caitlin and moved my right hand to her crotch. I slipped a finger between her pussy lips and began working it up and down her slit. Caitlin turned towards Rebecca.

"Like you, I prefer to be eaten but I mix in occasionally being fingered so it won't be same old, same old." She turned to me. "I don't think it will take you long. Last night, I got so hot watching you and Rebecca fuck while I advised. I felt like I was a part of the action."

Caitlin wrapped her hand around my cock, giving it a quick pump up and down, then dropped her hand down to my balls and gave them a light tickle. She turned back to Rebecca.

"It's a good idea to play with Thomas' privates while he's fingering you so he'll be ready when you're ready. Could you do that for me?"

"Sure," said Rebecca as she hopped off the bed then got back on behind me. I was on my side, tilted slightly away from Caitlin so her hand could play with my balls. Caitlin removed her hand.

"What should I do?" asked Rebecca.

"Play with his cock and balls," replied Caitlin. "Nibble on his neck. Whatever he likes. Don't get him too excited, but keep him hard."

Rebecca wrapped her right hand around my cock. Her hand was much smaller than Caitlin's and a little colder. She slowly pulled her hand up the length of my cock while rubbing her tits across my exposed right side.

"Do you like that?" she whispered huskily to me.

"Yes," I said in my normal voice.

"Do you like the hand or the tits?" she whispered. Her hand was making its way slowly down my cock.

"Both."

Rebecca stopped with the tit rubbing and instead kissed lightly down my right arm. Her right hand dropped down to my balls and cupped them.

"Do you like this?" she whispered. Her sexy whispers were driving me wild.

"I prefer a light tickle."

"Like this?" She gave my balls a soft tickle.

"God, yes."

She moved her hand back to my cock and gave it a light stroke upwards while rubbing her tits again against my side. She was doing such a great job of keeping me hard that I was having difficulty staying focused on my mission. Caitlin was excited enough now that I could mainly focus on her clit. Her eyes were closed and she was breathing deeply. I slipped my hand down to her vagina to get some more fluid and my hand was soaked.

"You're really wet, Caitlin."

"This is so fucking hot."

Last night, the cabin had smelled of sex. Now, it reeked. I was sure the sheets underneath Caitlin were soaked.

Caitlin grabbed my hand and pulled it up a little higher. "Right there."

I pressed hard on the new spot and made tight circles with my finger.

"Rub hard now. I'm close."

Rebecca had shifted up and was nibbling on my neck and blowing in my ear while stroking my right side with her hand.

"Yes! Yes!" cried Caitlin as she tensed her body in anticipation of her orgasm. "Yeeessss!" she bellowed as it hit her. From the way she flopped around, it was clearly a big one.

Rebecca had shifted back down and was stroking my cock again to get it back to maximum firmness while she ever-so-lightly brushed my side with her nipples.

Once Caitlin had recovered from her orgasm, she spun around to get on all fours and pointed her ass towards me. "Fuck me, Thomas," she commanded. "I need you in me right now."

I moved behind her, lined my cock up with her pussy and slid in. She was so wet that there was no resistance. I plunged my full length into her.

"Agggggh!" she cried.

I grabbed her heart-shaped ass, pulled myself out and slammed back into her. I skipped the slow stuff. If she wanted to be fucked, a fucking was what I was going to give her.

"Rebecca, this is doggie style," said Caitlin. She had paused between "Rebecca" and "this" for a pant. "It feels much different than missionary. You're going to have to experiment to find what works for you." Caitlin had to bunch her words together because of the pants, which made her sound more formal. She raised up on her hands and arched her back a little bit. "You can go up high." Then she dropped her chest down so that it was touching the sheet. "Or you can go low. There is no right way. Guys love to hold your ass and pound you from behind like an animal."

I certainly did. Caitlin's soft, round ass was perfect for doggie style.

"I'm so little compared to Thomas," said Rebecca. "He'll be too high up for me."

"Then don't do this while you're both in bed. Try having Thomas stand next to the bed. Or lay over a couch arm. Fucking someplace besides the bed is great way to add variety."

Rebecca stood behind me and moved forward until her chest touched my back. She ran her hands lightly up my arms, then across the top of my shoulders, then back down again. Her nipples were barely touching my back and she made slow circles with them on my skin. "Would you like to fuck me like this tomorrow night?" she whispered. "On the couch?"

"Definitely."

Caitlin apparently took that to mean that she had adequately demonstrated doggie style. When I pulled back, she pulled herself off me then stood up on her knees. "Lie down on your back," she ordered.

I happily complied, lying down on the left side of the bed to avoid the big wet spot. Caitlin mounted me, grabbed my cock and guided it into her. She put her hands on my chest then raised her body off of me so that most of my cock was out of her, then dropped back down on me. She went through the cycle a number of times. I raised my hands up to cup her beautiful tits. I got her nipples between my fingers and then made slow circles. Her tits were such a nice size for my hands.

Once we had a good rhythm going, she turned to Rebecca. "This is girl-on-top. Guys love it because the girl does most of the work." She faced me and smiled. "You like just lying there, don't you?"

"Hell, yeah," I said with a big smile.

Caitlin faced back to Rebecca. "I love girl-on-top positions as it makes me feel in control. Girl-on-top is even better on a couch. And as you can see, the guy gets to play with the girl's tits if he wants."

"Or fondle her ass." I dropped my hands down to Caitlin's ass and helped her rise up and drop down.

Caitlin said to Rebecca, "Why don't you play with his nipples."

Rebecca scooted around so that her head was close to my neck. She slid her hand down my chest until it reached my nipple. She pinched it lightly between her fingers.

"Like this?" she asked.

"Whatever Thomas likes. Think about what you like and do it to Thomas."

Rebecca tried different things - twisting my nipple, rubbing my nipple softly with one finger, making light circles around my nipple with a finger, stroking my chest in the area around my nipple. Each time she tried something different, she whispered in my ear, "Do you like?" Then she added nibbling on my ear lobe and kissing down my neck.

"Is this a good way to kiss and make up?" she whispered.

"Oh, the best. This is incredible." I was in pleasure overload. Caitlin was such a great fuck, then adding Rebecca's nibbles and strokes was mind-blowing.

"I think Thomas is getting close," said Caitlin. "Guys like to fuck hard before they cum and Thomas can't do that with me on top. So we're going to roll me over and switch to missionary. Ready Thomas?"

Caitlin rolled and I rolled with her. I swung her around to keep us away from the wet spot. Caitlin was right that I was close. And I did want to pound her hard to finish. I slammed into her and she slammed back.

"You can do some variations," said Caitlin to Rebecca, "by moving your legs into different positions. I prefer to keep my feet on his ass and use them to encourage him to fuck me harder."

Now that she mentioned it, I could feel her heels giving me little kicks on my ass. I was plunging into her as hard and as fast as I could. Her tits were bouncing up and down in front of me. She was thrashing around underneath me. This was our last fuck and it was going to be our best.

Rebecca was on her knees next to me, stroking my back as I fucked Caitlin.

"You don't fuck me this hard," Rebecca whispered.

"I can't. You're too tight. I love your tightness."

"In that case," she whispered, "fuck her hard for me."

That put me over the edge. Waves of pleasure hit me as felt the cum flowing up out of my balls.

"Yeessssss!" bellowed Caitlin as she came. My cum shot into her, binding us together once again in the special way that only hot sex can do. I slowed the pace as I came and came. Finally, I stopped to savor the moment. I looked down at my beautiful sister blissfully stretched out beneath me.

"I love you, Caitlin."

"And I love you, Thomas."

Caitlin pushed me so I pulled out of her. She turned to face Rebecca.

"He's yours now. You better keep him happy."

"I will," said Rebecca as she put her arm around me to give me a hug. "I will."

Epilogue - August

And she has. Sunday night when we got to Rebecca's apartment, we packed up a few days worth of clothes and she moved in with me. We've slept together every night since.

Tuesday night, we went back to her apartment and packed up more until it was time for the video call with her parents. Rebecca started the call by saying "This is Thomas. I love him, I went on the cruise with him and I've moved in with him." The band-aid was ripped off in record time. Her parents were stunned. For the rest of the call, they were subdued. Most of the call was introducing me. When they asked about the cruise, we kept to the script that we had developed with Caitlin. Rebecca then said, "I know Thomas is the right guy for me, but we have some emotional wounds that need healing. Would you please pray for that healing and for the strengthening of our relationship?" Her parents gave a long prayer for that and I was touched by their sincerity.

The next Sunday, we started our search for a church that we both liked. We spent months visiting different churches. As part of the search, Rebecca and I had many long discussions about what we believed. We both believed that God wants us to be frugal to ourselves; loving of our friends, family and neighbors; and generous to those less fortunate than ourselves. As a part of that, we discussed the big topics - how we wanted to live our lives together, what our career goals were, whether we wanted kids, when we wanted them and how did we want to live once God blessed us with them. It turned out that once we moved beyond labels, we were spiritually quite close. We've recently found a church that has many people our age and has been quite welcoming. We're thinking of joining soon. Rebecca's parents seem more disappointed that she's going to join a non-fundamentalist church than that she's living with me.

Caitlin is doing well. On her flight back from Miami, Jacob suggested that they get back together like Rebecca and I had. Caitlin laughed so hard she nearly peed her pants. Caitlin moved in with Lisa. With the reduced rent and a nice raise, she is making a big dent into her debt. She's had several opportunities to date but has been going slow, researching each guy and has yet to find one she thinks is worth dating.

Rebecca and Caitlin talk on the phone all the time now. It started when Rebecca called for a few more sex tips, but their friendship really took off once they started discussing work. Caitlin has been coaching Rebecca on how to be more assertive and Rebecca has been coaching Caitlin on how to better market her bank and herself. They have both gotten kudos from their bosses for improved performance. When either has a bad day at work, they pick up the phone and call the other to vent and strategize. Rebecca tells me that it's easy to have a meaningful conversation with Caitlin because Rebecca knows that nothing she tells Caitlin is going to shock her or make her think less of Rebecca and me as Caitlin already knows all of her darkest secrets and still likes her.

Life with Rebecca is great. She's still not comfortable kissing in public, but has grown fond of hugging, cuddling and sitting on my lap in public and in front of our friends. Our sex life is much better. Frequency is up. Communication, variety and enjoyment are way up. It's not like sex with Caitlin, but we both wind up feeling loved and satisfied.

On the Fourth of July I proposed, Rebecca accepted and we are going to be married in her hometown the week before Christmas. Caitlin will be the maid of honor. Paul is going to be one of my groomsmen.

I think often of Caitlin. She was right in that there was no way we could logistically continue our relationship. I believe that things turned out as they did on the cruise because Caitlin and I were cruise-compatible and Rebecca and I were not. In Boston, Rebecca's sweet and easy ways fit me better than Caitlin's blunt, earthy style. Still, there are times - particularly when Rebecca isn't in the mood for sex - that I fantasize about what would have happened if Caitlin and I had tried to make our relationship work.

Caitlin is going to visit us for five days over Labor Day. Rebecca and I bought her the plane ticket. It was Rebecca's idea - she wants some more in-depth sex lessons.

I can't wait.

Author's Notes:
* A huge, huge thanks to my editor AnnaLinguist, who did yeoman work suggesting improvements and correcting my many mistakes in this monster
A big thanks to my beta-reader Gunter99
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