The woman concentrated for a moment, and she began to shrink, going backwards through her teenage years. Her breasts going from full, to budding, to nonexistent, and her frame shrinking until she looked like a ten year old girl, her hands easily slipping out of the handcuffs. She made to return to her old form, but then had second thoughts. Someone had handcuffed her and left her there. It may have just been an absent-minded sexual partner, but with no memories, she didn't want to chance it being something more sinister. If she remained this size, she'd have to find more clothing, but no-one would recognize her. She looked in the wardrobe in the room, and found some spare servants clothing that were sized for a sixteen year old.
Looking in the mirror in the room, she aged herself up to sixteen, and put on the outfit, adjusting her proportions until the outfit was a perfect fit. For good measure, she also changed her hair colour to blonde, and added a sprinkling of freckles to her face. Hopefully, that would be enough to make people overlook her.