The only really noticeable change, as far as Jon could tell, was that the room was now scattered with Matt's stuff. Various articles of his clothing were strewn about the assorted horizontal surfaces available. Jon was a little put-off by this; he was a little bit of a neat freak, at least compared to his brother. He set about gathering up the different clothes, then took them to the closet and tossed them in the laundry basket, on top of the bra and skirt that were already in there.
Wait, what!?
Jon dug through the basket. In addition to Matt's dirty laundry, there were a brassiere and a medium-length skirt in the laundry. Suddenly Jon had a suspicion that things had not gone quite according to plan. A quick check revealed that this was correct: Jon was a woman. A very tomboyish woman, with small breasts, short hair, and a fairly boyish figure, but undeniably female. Though she was wearing the same shirt and pants she had been, underneath it was panties and a bra, and from the laundry basket, it looked like she had more traditionally feminine items in her wardrobe as well. She rummaged through her dresser drawer, and found an assortment of clothes that covered most bases, but there was a pretty obvious preference towards gender-neutral clothing.
This was not what she had intended. She was about to make a wish to try and fix things, but at that moment Matt walked into the room. He chuckled. "Oh, Jonni," he said, smiling. "Baby, I know you probably feel a little awkward living in my parents' house, but you don't need to feel bad about a little mess. I've lived with them all my life; they know better than to think that the sloppiness reflects on you, hon."
Jon...Jonni stared at him. His parents? Then was he not her brother any more? Instead of changing society to make their marriage acceptable, it had changed her! She wondered who her parents were now, but her thoughts were cut short when Matt emmbraced and kissed her. As much as this had not been the plan, Jonni couldn't deny that it felt good. After all, they were supposed to be happily married.
...and with an active sex life, she realized.