Jessie was training to be a doctor like her brother before the world ended.
Jessie is skeptical of people, since mostly everyone will use you for their own gain. She will help you with your wounds and be on her way if she can help it. Provided your wounds are treatable, bud.
Jessie carries around a bag of medical supplies, even though her supply is dwindling.
In the way of weaponry, Jessie Carries around a hand ax and a kitchen knife. Before the war, she had taken up throwing knives. Aside from that, she carries a backpack with various food stuffs and other random supplies.
Having lived in England her whole life, Jessie was surprised when war was declared. When her brother was killed in a terrorist bombing, she blamed herself. To this day, she wonders why anyone would want to kill a doctor.