Being a pre-teen kinda sucks, on top of school, puberty, now your parents are saying you have a new big sis? Everyone else buys it but you know the truth. She told you she was you from the future. The device she used made everyone think she was your long lost sister and prevents the universe from exploding if you touched her.

If the device also didn’t make you believe it you probably wouldn’t have. You? A girl? Of course you denied it. But she said she had chosen this time for a reason. She knew what you had seen on the internet and what you did in the showers thinking about it. How bad it made you feel to want things you could never have. She said you could have those things, but you realized it much too late. Her timeline was doomed. She hoped to fix that by messing things up here.

It turns out having a your future self guide you through school helps a lot. You could never talk to your parents about anything. None of your feelings, nothing deep about yourself. They knew and would always only ever know a very surface level you, but your sister? She knew exactly what you were going through.

When you were getting bullied she taught you how to fight. When you were struggling to do assignments she helped give you motivation. And when you didn’t know why you were so upset at having to shave, having your voice deepen, growing hair in parts you didn’t want hair in, she gave you medicine to make it stop. She never forced it on you, she knew you would have to experience it yourself first. 

More and more you found yourself going to her for everything. She drove you places. Showed you things. She was changing too, subtly at first. She had to shave her face less the more you stuck with the meds. A new scar from a new fight appeared in the same spot on her arm as she bandaged and tended to yours. And shamefully to admit, you were still a pre-teen after all, you grew jealous of her bust as it got fuller and slightly bigger.

She had to know the glances you were making at her body. You were obsessed with it. She had already proven time and time again that she was you. She kept her distance, but you longed for her, and the more you did the more you knew that she did as well. Slowly, like a glacier melting, she couldn’t help but close the distance.

You looked at yourself in the mirror. You had been a chubby kid, but with her help you actually had the motivation to exercise, and she taught you how to count calories and not overeat. In just a few years you had gone from chubby kid to androgynous teen(still a little plump, but you liked it like that because she liked you like that). She taught you how to care about yourself. She told you about how it was for her without “her”. How the pieces were there but she didn’t have the puzzle box to see the whole picture. How she wished someone could have just told her what to do.

She gave you the confidence to face the world as you. As someone sure of who they were, of what they wanted, who knew how to get it, and could go for it. It felt like playing life with cheat codes on. She had to know this, so strange then that when what you wanted was her, and you went for it, she looked shocked. She recoiled from your kiss and your touch after. You wondered what she was feeling, did she remember this moment now?

She must have, because she didn’t leave. The door was closed and you took a step towards her, and another, and with each step you could see her resolve melting. You touch her again, gently lifting her shirt, running your hands along her stomach. You look into her eyes and realize, she’s not you. She may be affected the changes she was making to you but you would never grow up to be her, couldn’t grow up to be her. In her eyes you see the lost scared child you could have been, that she was.

You embrace her, nearly as tall as she is now, and gently brushed her hair on the back of her head with your hand. She had been so strong for you. She had built you up, and now you could be strong for her. You tell her its ok, that you want this as much as she does. She tries to go on and explain how somehow she was manipulating you, that somehow she had groomed you into this. “That’s not how the changes worked,” you explained. “What I do affects you, not the other way around.”

Tears streamed from her eyes, your big sisters eyes. You kiss her on the lips, a kiss of caring and reassurance, and finally she wraps her arms around you. Sobbing she cries, “I love you, lil sis..”

“I love you too, cool big sis.” You say.

The kiss that comes next is one of passion, of great release, of the glacier sliding free fall down the side of the mountain. You take the lead, pinning her on your bed and kissing, but you’re inexperienced despite your confidence. She smiles and guides you. Your clothes come off as do hers. She shows you how to touch, where to touch. Now you’re on your back and she’s licking around your crotch, teaching you about sensations you never dreamed of.

That area is so sensitive to you she doesn’t even have to touch your cock to have you screaming a bit too loud. She smiles devilishly as she shushes you. She’s eager to teach you more about your body. You knew some things, but she had years to refine her understanding. With a bit of lube and her fingers in your ass and a gag in your mouth she made you cum more times than you thought possible. When you recovered she told you to try it on her.

So you mimicked her, massaging her tits which were at least three cup sizes bigger than you still. Putting your hands over all the sensitive areas she showed you and delighted in watching her squirm just like you. The gag in her mouth was wet with drool. You weren’t sure how to give a blowjob yet, but you sure as hell knew how to jerk yourself off, so that was easy to do while you figured out the fine details of prostate stimulation. 

In the end you were both exhausted, naked, and she held you in her arms as you drifted off to sleep. Before it can take you you hear her giggle and say, “You know I always wanted a sister.”

You laugh too and say, “Me too.”