Rachel made it home that night in high spirits then groaned as she came in the house and saw the one person she disliked the most in the world coming down the stairs...her sister Abby. Abby was a stunning blonde with hair that reached her butt and fell in gentle waves the whole way and her face was perfect with large green eyes and a cute little nose and a perfect stunning smile. Her tits weren't huge a nice D cup that fit her slim tall frame and her waist was small but flared out to large hips that rounded down to her long shapely lags and Rachel hated every inch of this godly looking sister of her and her cock betrayed her as it grew several inches down her legs as she saw her sister saunter down the stairs.
"Hello Rachel! I just got unpacked into my old room and I'm so glad so see you!" She said as she hugged her sister causing Rachel to grow a few more inches, any more and she'd start to show!
"Hello Abby." Rachel said in a monotone. "How long are you here for?"
"Oh about two weeks our campus was shut down due to and outbreak of sickness and they didn't want to take any chances so hear I am a week early for spring break!"
"Oh joy!" said Rachel with a wicked grin as she pulled out her phone and called Jasmine "Hey my sister's home early think you can come over to my place instead?"
"Sure no problem just let me eat and pack and I'll be over around 7?"
"That sounds great!" Just then Rachel's mom Ashley appeared around the corner. "Hey sweetie isn't it great we have Abby home for two weeks! Oh and this letter came for you in the mail." She said holding out an envelope.
"Thanks." Rachel said taking the letter "I'm going to go to my room and change and I invited Jasmine over again ok?"
"Alright honey you two girls have fun but keep it quite ok?"
"Yeah sure got it." Rachel said absently as she climbed the stairs. When she got to her room she dropped her backpack and removed her shirt and pants, her cock still half hard and drooping out from her crotch almost 20 inches long, and popping off her bra to release her huge E cup tits and sighed in comfort as she sat on her bed and ripped open the envelope. Out dropped another ring just like the one Jasmine wore that started this whole thing! Rachel slipped it on and pulled out the letter inside and found that this ring was just like her last one allowing her to change herself as she wished but also able to change other people, but was limited to line of sight of the person intended to be changed. Rachel grinned as her mind raced but her cock needed tending if she was going to make it through dinner and she walked to the shower and got off her massive 30" prick fairly quickly thinking of her perfect sister and what she wanted to do to her tonight. Despite the quick orgasm her load was still huge as it filled the shower to her waist in one load and she had to wait for the cum to drain and rinse off before she could exit. Before she got dressed she grew her cock to a massive length of 12ft a size she had reached only once before and planned to have some fun at dinner as she also made it prehensile. She came down in sweats and a comfy loose t-shirt her cock hidden under the baggy folds of her sweats.
"Dinner's ready" Her mom called from the kitchen and Rachel sat across from her sister. As they ate Rachel snaked her cock out across the floor under the table over to her sister. Her sister was wearing a light sun dress luckily or unlucky depending on who you are and she wore no underwear as she didn't want the outline of panties to show against her perfect butt. Rachel knew all this and grinned as she felt her massive cock lift up her sister's dress and snake up to her pussy where she slowly entered her sister's pussy. She gasped softly unprepared for how tight and warm her sister was as she sunk deeper and deeper into her sister's pussy. As she did Abby gave a slight yelp of suprize and a jump as she felt what could only be a cock enter her pussy and a big one at that and she felt it go all the way inside her. Abby was able to pass the yelp off as biting her tongue and looked across the table and she didn't know how but she knew this massive cock inside her was her sister's.
Rachel was suprized by how much of her cock her sister could take she could see the tip of her cock reaching between her sister's tits as she thrust in and out of her sister's pussy and given how tall her sister was that was almost three feet of her cock she was taking! As Abby was forced to answer questions about school and such Rachel assaulted her pussy and Abby was trying to remain unfazed as her orgasm rapidly approached from her sister's massive cock. Finally a lull approached as her parents discussed work and Abby let her orgasm, one of the most powerful she had ever experienced, wash over her and she shook slightly for several minutes biting her tongue to keep from moaning or screaming in pleasure. Rachel could feel her sister's pussy contract powerfully around her and kept fucking her hard as she came. Rachel wanted to finish too and let herself cum but had taken care to restrict her balls to normal sized balls when she made her cock 12ft long and as such her now 15ft cock still soft, she had to grow to fill her sister's pussy, came a small load of almost 15 streams but still large enough to stuff her sister full as Rachel retracted her cock. They finished dinner and Jasmine arrived shortly after and they went up to Rachel's room. Rachel was aware that Abby's eye's tracked her as she moved and made sure she saw that large bulge her now 3ft soft cock made as she inflated its girth to as big as her thigh as she moved up the stairs returning it to normal as she enter her room. Rachel returned her cock to its previous state that she had it at dinner that evening letting it grow longer and right out the bottom of her pants as she sat on her bed as her cock return to it 15ft soft form.