One of the things sold in the shop was a pair of shoes.
These shoes have a special power.
When holding both of them in the hands, the shoes can change to whatever size the person has and to whatever style he/she wants them to be.
Only the one who makes the change will notice the changes of the shoe, while the others would think the shoes have always been that way.
However, that change can only occur once a day, with one only able to do so again the next day and at least 12 hours after the last time it was done.
For example, if one used them that way at 8am, he would have to wait to midnight to do so again, and if one used them that way at 11pm, he would have to wait until 11am the next day to do so again.
When a person wears both shoes, he/she can change them both freely to whatever type he/she desires, without a time limitation. No matter what type is chosen, the wearer’s “standing height” will always stay the same, meaning that the height of the shoes would be added or taken from their wearer.
Once again, only the wearer would notice the change of his/her stature and the style of the shoes, but in addition to that, reality would change to suit his/her new stature in both clothing and furniture, but it would not change any other living being physically.
For example, if a woman changed the shoes to 2 inch heels before wearing them, and then changed them to flats while wearing them, she would gain almost 2 inches in height (flats still have soles), and her clothes would change to fit and everyone else would think that it is normal for her to be that height, and if she desires, she can change them right away to 4 inch heels, which would make her two inches shorter than her original height, and reality would once again change to fit.