The old woman is a citizen of the village closest to the Hallowed Tower. When Spiritomb was let loose by Ash and his Buizel, this woman told him and his friends the tale of Spiritomb, and how the Aura Guardian sealed him away. The group decided they would help seal Spiritomb away just like in the legend, and the old woman followed them, occasionally giving advice.
However, she displayed some anger towards the group at first when finding out that it was them who smashed the towers. She believes Team Rocket to be "dumber than they look."