Just then, my adopted sister Erica walked by my room.
Erica hadn't grown up with Zoe and I; she had been adopted only a few years ago after she fled from her abusive family. We actually shared the same birthday, and were the same age.
When our parents weren't around, Erica shamelessly flirted with Zoe and I, having no taboos against such things. Today, I decided I would take her up on it, my way.
"Erica, come in here, close the door and be silent."
She walked in, confused, and sat on the edge of my bed.
"Erica, you can talk but only softly and only to answer my questions. Erica, you must answer my questions truthfully. Was your flirting actually serious?"
"Yes," came the quiet answer.
"Given the opportunity, would you go all the way with Zoe or I?"
"Yes," said Erica again.
"Erica, I want you to cause time to stop except for the two of us and then lose your ability to control time until I tell you to use it again."
Just like that, all sound from outside the room ceased. A look out of my window showed cars and pedestrians frozen in place.
"We have the opportunity now. Will you have sex with me?"
"Yes," she said, even more quietly this time.
"Then, Erica, strip, sexily."
It was a warm day, so Erica wasn't wearing much. She peeled her top off slowly, revealing her bra inch by inch. Next came her Daisy Dukes, which provided her with the opportunity to wiggle her thong-clad butt suggestively in my direction. One breast at a time came out of her lacy bra, and finally her thong panties came off, and she tossed them in my direction. I looked at them briefly before tossing them aside and feasting my eyes on her form.
It was a very nice body, but there was room for improvement.
I decided to get naked myself, partly to relieve the pressure on my erection. While doing so, I asked another question. "Since we're going to have sex, can I touch you in sexual ways before that?"
"Yes."
"Erica, except for the hair on your head, your eyebrows and your eyelashes, cause your hair to fall out and the follicles not to exist."
Moving over to Erica, I ran my hands along her now-smooth body. She shivered as I verified that even her pussy was completely hairless. I put my hands near the small of her back.
"Erica, grow your hair to here, in two braided ponytails, then stop growing it." Her hair grew until it reached my hands, forming into two parts and braids by itself.
"Erica, each time I smack your ass, grow it out an inch until you've grown it eight times in this way." While deciding what to change next on her, I slapped her butt at random intervals until I counted eight and her ass was huge.
I put my hands around her waist. They couldn't quite reach each other. "Erica, shrink your waist until I can wrap it with my hands, then stop shrinking it." Her waist shrunk beneath my hands, stopping not long after.
My next command was for her chest. Her breasts were nice, but not as big as I'd like. I held my hands out from them at what I estimated was a J-cup for her. "Erica, grow your breasts until my hands make a one-inch depression in them, then stop growing them."
The onslaught of breast growth actually managed to push my hands back a little before I started to press in. Getting down an inch proved a bit difficult, as the growth was rapid enough, but eventually I stopped them at what might have been a T-cup or a U-cup if such sizes existed. They were the size of small watermelons and hung deliciously.
"Erica, have long sexual stamina with near-instant recovery time and make anyone who has sexual contact with you have the same." She appeared to shudder slightly, and as I brushed her nipple, so did I.
Then she fulfilled her promise to me, and we screwed like bunnies. With time frozen and our ability to have sex almost constantly, we had no idea how long we were actually taking. Finally, I said, "Erica, that's enough." She rolled off me and lay next to me.
"Erica, don't get pregnant or have any other ill effects from what we did. Erica, return to your original body. Erica, get dressed, then unfreeze time and lose the ability to control time until I tell you to use it again."
After getting dressed, Erica looked at me and spoke without compulsion for the first time. "Can we do that again, Jon? That was amazing."
"Maybe. Will you tell anyone about this time, or any other time?"
"No!"
"Then perhaps. For now, Erica, forget about everything that happened since you came into my room."
Erica shook her head. "What am I doing in here?"
"Oh, nothing. You should probably finish up getting ready for the day."
She smiled at me and left.
I couldn't wait to try out some of what I'd discovered I could do on Zoe and Erica on other people.
