>>939793763
I was 12 when we started the loop and 13 when we ended and she is a year and a half older than me.
I dont remeber everything in super great detail but I can give you a tl;dr and you can ask away from that. So like I said, we lived on this boat for almost year and with the consent changing in and out of lounge wear, swim wear, formal wear etc etc in such a small area multiple times a day, you are bound to stumble upon each other naked. Eventually you just stop caring and get pretty use to changing infront of or around other people. That goes for sleeping as well. Some nights were hot and you would be sleeping in next to nothing but eventually got use to sleeping naked. My sister and I shared a cabin like the one (not an actual picture of our boat, just same model) in pic rel, so we got a pretty good look at each other. At first I would just jerk off in the washroom but laziness and horniess got the better of me and would try to sneak fap at nigh. Im assuming my sister must have felt the same way because I would start to notice her doing it as well. At first I would stat dead silent but one night while being horny I decided to jerk off at the same time. We kept pretty descreet about it but masturbating at the same or close to the time kind of became common. I eventually got horny to the point where I was trying to slide down her panties to give me something to jerk off to and got caught. This lead to an awkward conversation but her sleeping more poractive afterwards. We eventually moved from masturbating beside eachother, to watching eachother, to petting, to oral. We never had sex but pussy slides and humping her ass and thighs became quite regular. Some nights we would make hot hard for hours, others i would just be 3 fingers deep in her, nut and go to sleep. After we finished the loop and back to normal life, everything sexual between us stopped.