Immediately after the salt touched Jezebel, she began to change into the type of person Jon most desired for her to be, which was obviously Jon himself. Jon knew that he wouldn't be able to get his body back to normal with the stone, thanks to its inability to reverse wishes, but with the Salt of Desire, Jon could make any desire come true. There were no restrictions.
Unfortunately, he didn't just desire Jezebel to have his body. He desired her to be Jon Gibson, meaning she had his body as well as his mind. She really thought she was Jon. Essentially, his sister Zoe was now gone. All that was left was her body, which the real Jon now possessed.
"You're gonna give me that salt, Zoe," the new Jon ordered.
"I'm not Zoe!" Jon yelled, hoping to get the point across. Hoping that the new Jon would remember that just moments ago he was Jezebel and before that was Zoe. But it didn't seem to work.
"Nice try, but I'm not falling for that. I wish ..."
