Bathsheba, often called Bats for short, was a young girl, about thirteen years old, who lived on a farm on Tír na n-Óg. Due to having a withered right arm since birth, she was unable to do much work on the farm other than gleaning the fields or gathering firewood. It was also suspected that she might be a demon and would develop a witch mark, in which case she would be burned. She hoped to someday meet Goibhnie so that he would cure her arm.
Shortly after Dagda's Wheel disappeared and the demons from Goibhnie's island were freed, Bathsheba's family was killed by demons while she was out getting kindling. She stayed at the farm until it was visited by the Seventh Doctor and Ace, who were on a quest to see Goibhnie, and joined them. The Doctor later tried to leave her with Chulainn to avoid putting her in danger, but she followed him anyway. When she finally encountered Goibhnie, she was crushed to learn that he was unable to cure her arm, as he no longer had any protoplasmic material. After Dagda's Wheel was restored and the demons destroyed, the Doctor left Bathsheba with Dryfid before returning to Earth. (PROSE: Cat's Cradle: Witch Mark)