u/midwestsfinest_

At this point I'm not sure what to do. My sister is actively rubbing her pussy along the shaft of my cock and teasing the tip every once in a while. It feels like it goes on for hours, but in reality it's only been a few minutes. I can't keep letting this go on like this. We've never pushed it this far before and I don't know if this is something I really want to commit to in the moment.

M: My head is feeling better now. I think whatever you did worked. You don't need to keep going

H: Are you sure? It looks like someone else wants me to keep going

M: Yeah. Let's take a break and get out of here. I've been in here way too long and I can feel my skin wanting to fall off

H: Whatever. You're no fun

She gets up and out of the hot tub, grabs her towel, quickly dries off, and turns to leave. Before closing the door behind her, she looks over her shoulder and says -

H: I'll be upstairs in my room finishing what you started

And then walks away. I take a minute to collect myself before getting out, drying off, and going to the kitchen to get something to drink and eat. I look at the clock and realize that it's been almost an hour since we got back. The rest of our family is probably nearing the half-way point of the hiking trip and we've still got 4 hours or so left to ourselves. I'm still bricked up and standing in the kitchen and I can hear my sister moaning from her room upstairs. It's been a long day so far, I haven't had much to eat, I'm feeling slightly lightheaded from being in the hot tub for so long, and I look over at the bottle of tequila my parents brought with to the cabin. I say 'fuck it', I take a heavy shot, and I go upstairs and walk into her room.

M: You weren't kidding from earlier. My balls are killing me from the procedure

She's facing away from me, face down, ass up, and fingering herself. She pulls her fingers out, points at me, and curls her fingers to lure me in. She slaps her soaking wet pussy and says -

H: I have the cure right here

M: I'll give you a tip as big as you want as long as you keep making me feel good

H: Oh, so you admin that this feels good?

M: Very. Although I am getting a throbbing pain in my head now

H: Oh no! Let me see if I can fix that

She stands up, turns around, and straddles me. She leans in and kisses me on the forehead.

H: Does that feel better? You know how mom and dad used to always give us a forehead kiss when our heads started hurting

M: Right, that was nice. And thank you for that. Both that wasn't the head I was talking about

H: Oh, you mean this one?

She places both hands on top of my hands, which are still covering my cock

H: You're not letting it breathe. You should let go of it so the blood can flow properly

She pulls apart my hands to expose my cock and cradles my balls in her hands

H: Even under water these are so heavy. You must have so much in here

M: What are you going to do about it?

H: Well nothing, obviously. You said your head was hurting, not your balls. Or at least they aren't hurting yet

M: What do you mean by 'not yet'

H: I have plans to make your head feel better but I don't know what the side effects might be

She starts rubbing the tip of my cock with her thumbs.

H: It's weird. Even though we're underwater, I can still feel your precum. If we keep this up, we might accidentally overflow the hot tub. There's so much coming out

I'm leaning back while she continues to "massage" me and she adjusts herself and starts rubbing my shaft with her pussy lips.

M: Don't get any weird ideas while you're down there. You know sex underwater doesn't work

H: I know. It's like sneakers on a basketball court. Water isn't lube

I reach out to start groping her tits but she smacks my hands away.

H: The doctor is busy. You shouldn't distract me when I'm doing such a delicate procedure

M: What's the procedure again?

H: I'm making your head feel better, dummy. But in exchange, your balls are gonna hurt so bad unless you do something about it

My fully nude sister slides into the hot tub across from me and runs her foot up the inside of my right leg, stopping at the knee. She traces up and down my leg a few times while making eye contact with me and not saying a word.

M: This isn't really the kind of massage I expected.

H: Oh, and what were you expecting?

M: A massage with your hands. That would be a start to an actual massage. Not whatever you're trying to do, or planning on doing.

H: Silly me! Let me come over there and do it properly. It's my first time though, so let me know if I do something that makes you uncomfortable.

She pulls back her leg, stands up, walks towards me, turns around, straddles my right leg, and places both hands on my knee and starts rubbing it.

H: How's this? Is this better?

Flustered, I sit there quiet and let her have her fun.

M: Hm...

H: Don't be shy. You can tell me how I'm doing. I can even massage your thigh for you too, if that helps relax you.

She starts grinding her hips up and down my thigh and using that leverage to put extra pressure on my knee.

M: I thought you said this was your first time. This seems like an advanced technique.

H: I'm a quick study. I've seen a few videos here and there. I know how your knees are so I watched some videos on massages just for you.

M: You're so considerate. And lucky me, I don't need to go anywhere to pay for a massage. I can just ask you from now on.

H: Mm-hmm. I won't take payment from you, but I do take tips.

M: Tips? How much am I supposed to tip without knowing how much the service is?

H: Just the tip of a your tip, maybe. That should be more than enough. Call it a discount for being my first customer.

M: Seriously, that's what you're after? You've gotta be joking.

H: I can stop and move back over to my side of the hot tub if you'd rather.

M: That's not what I'm saying.

H: Well then how big of a tip are you willing to give me?

Thank you all for the interest and messages about my last post. I'll keep my 'about me' on my profile updated with frequently asked questions. You can also check my profile for previous parts of this story and more!

I'm in the hot tub relaxing my knee from my hiking failures. I've been there for some time and my sister walks outside to check on me. She places her towel down on the stool next to mine and sits on the edge of the hot tub across from me. This isn't anything special or crazy. We've all seen each other nude multiple times in different situations, so it's just another day at this point. She's sitting cross-legged and not flaunting herself in front of me. Remember, I come from a nudism family that isn't orientated around sexual activity, but rather freedom and acceptance.

H will be for her, M for me, B for brother.

H: I had a right to be worried about you. Why is this thing so hot??

M: I like it that way, I can feel myself melting.

H: I don't know if I can get all the way in here like this. You and B always crank this shit up all the way to keep the rest of us out.

M: Well then you can stay out there. Not my problem.

She brings one leg out of the water and on to the ledge of the hot tub to help cool down and not keep so much of herself in the water. At this point, she's fully exposed and I can see nearly everything. Being younger during this time, I get excited at the scene and start getting aroused. I remove my arms and hands from the side of the hot tub and put them underwater to cover myself, for decency.

H: Woah, woah, woah. What's going on down there? Did I just get you going from that slight movement?

M: Shh, it's nothing. The heat is making me light headed. I should probably get out of here anyways.

H: No, no, no, you stay there. Why don't I come over and massage your knee underwater for you. It is still hurting after all, isn't it?

M: It's feeling better now. I don't need a massage.

H: Shh, it's nothing - she mocks, and slides in the tub

For context, my family regularly goes on vacations. Ever since I was younger, we would take about 3 trips a year around the USA to various national parks and towards areas of interest. I've shared a little background on my profile about my upbringing in a nudist family, so feel free to read that for more context about my family and our level of being comfortably naked around each other.

We love visiting the mountains. We visit both the Rocky Mountains and the Appalachian Mountains pretty frequently and go on long hikes that take us nearly all day to complete. Sometimes I'm not able to complete the hikes because my right knee will start hurting during the hike and I need to turn around before it gets even worse. I work from home, and while I workout enough, I don't walk or do cardio enough. This was one of those times where I needed to turn around and go back to the cabin. My family always brings two cars wherever we go - for emergencies, and to make sure that if we get into an accident, we don't all die and there's at least some survivors left. I told everyone that I needed a break for my knee and we sat off on the side of the path for about 10 minutes. Afterwards, I tried to continue but after another 5 minutes I knew it was time to call it quits. I told everyone I was going back. We were 2 hours into a hike that takes 8 hours total, so nobody was super excited for me, or wanting to go back. But through her good heart and caring personality, my sister decided to turn back with me and make sure that I got back to the cabin safely.

Back at the cabin I decide that maybe some heat will help calm my knee, so I get in the hot tub. Nearly all cabins have a hot tub, and if it doesn't then we completely avoid it. I like stewing for a long time, and after a while, my sister came to check on me to make sure I wasn't frying myself alive. Clearly she also wanted some time in the hot tub because she was naked when she came to check on me. I'll continue this in another part!