His mother

After she watched her kids leave the dining room, John's mom turned around to clear the table, and noticed a notebook she had never seen before. Opening it and reading the intro and the rules in place, she recognized her husband's handwriting, and figured she could add to it. She wanted to support her son's desires, after all. After a bit of thinking of what to add. She added the following rule:

My son will have the body he always wanted, and the rest of the world will know he always had it. Only he will remember how he used to look. However, his heart and personality will remain untouched and his popularity will not go to his head. He will not be arrogant or conceited beyond what he already was. Any girl who he is romantically interested in will find him attractive and will enjoy giving him orgasms, but only ones who enjoy his fetishes will want to date him and have conventional sex with him. If every part of his body pleases her, she will be interested in marriage, but only if both she and my son are ready.

She tried to cram as much indirect specifics as possible because she was afraid of the age old genie trick of giving the person what they asked, but in a twisted way. She hoped being as specific as she was didn't somehow negate her rule. However, her concern vanished when the book teleported away to the next recipient.