Now
John 3’10” Allison 6’4”
John felt like his heart was going to beat out of his chest. Allison was his sister. Adopted sister, but still...his sister. Could he really…be with her like that? He had to admit he thought about her allot. Allison had become so big and sexy. When combined with his shrinking, his sister had turned into some kind of giant Babe Rex!
He cleaned the table. John wanted to make sure the job got done well. The last time he hadn't cleaned up right, Allison had bent him over her knee and spanked him. He walked out of the now perfectly clean room and entered the wash room. Allison's dirty clothes sat there in a bin, waiting for him.
As he'd shrunk, doing the laundry became increasingly difficult. Under four feet tall, he needed a chair to climb up to the washing machine proper. Standing beside the chair, John picked up the basket and lifted it, his little arms shaking. He managed to get it onto the dryer. Next, he climbed the chair so that he could load the clothes.
He paused as he held one of Allison's bras in his hands. The smooth fabric brushed gently against him. He held it up to his head in awe. One cup would swallow his head! Putting it into the washer, he picked up the next article of clothing, her panties. He could still smell Allison's scent on them. Blushing in shame as his member hardened, he put the panties into the washer and slammed the lid shut. Finishing his chores, John tried to will his throbbing erection down.
Finally, with no more excuses, he headed up to see his sister.
John entered her room. It was amazing how big it now seemed. He had used to think it was cute. Painted and adorned like any teenage girl's room. Now it had changed little unlike its occupant. “Uh, Ali,” he said looking to her private bathroom. She must have been getting ready for bed. He wanted to leave. "No," he thought, "I can't let myself live in fear." He resolved to sit here and wait.
Finally, Allison responded from behind her bathroom door. “Johnny,” she said, “Grab some air bro, I’ll be right with you.” He was locked in now. John couldn't leave without disobeying her. Looking around, John decided that her bed was his best option. Its edge was high up off the ground, meaning he was going to need to climb. Finally sitting on the edge he waited.
Eventually the door to opened and Allison stepped out. He couldn’t believe his eyes! His sister was standing in the doorway, wearing only a bra that contained her massive tits, a tiny thong, and a pair of heels. Why she wore them he had no idea, wasn't she tall enough? In them his sister must have been 6’7” or so. Her head was very near the door frame. She walked over to him with one of her smug smiles. Her broad hips swayed wide and her large, exposed tits jiggled and bounced. Finally she reached a point just in front of her shrunken brother and stopped. She placed a hand on her cocked him and tossed back her had.
“So, shorty,” she paused, letting him process all of her.
John gulped. “Y-yeah big sis.” he stuttered. "Are you ready for bed, little brother." He traced her giantess body. “Allison, we shouldn't…”
"Ut," Allison pushed her finger onto his lip and leaned forward. Her huge cleavage spilled out and up in her bra. John could lose an arm in there, if he wasn’t careful! He couldn’t believe just how busty Ali had become. The bra had to be custom made, Allison had long ago surpassed the kind you could buy in stores and now required special ones. Her rubbery flesh called to him and he looked away. If he came on her, he’d shrink again. Was that her plan, wasn't she big enough?
“Ali,” he said, “I-I don’t wanna shrink.” She smiled and lowered a hand. “Of course,” Allison picked John up and stood him on the bed. He couldn’t believe how strong she had gotten. Sure he’d shrunk but still.
Allison reached behind her and fiddled with her strap. “I think its time to tell you everything, John.” She succeeded in undoing the strap. “But first,” she reached out and took the back of his head. “I need you to listen to big sis.”