Rosebeth is the petrified girl just outside of Majula. You eventually need to free her as part of the story to move to the area she blocks but you can technically free her at any point once you have a fragrant branch of yore. You find these during the game but they are rare. You can buy one as early as the Forest of Fallen giants as the merchant you meet there sells one for 14,000 souls. She eventually moves to Majula.
When you free Rosebeth make sure you have some spare clothing in your inventory and she will ask you for some. The trophy pops as soon as you give her the items.