Agatha Faversham

Agatha Faversham was the daughter of Charles Faversham. After the death of her father she lived alone in their ancestral home until strange noises in the attic drove her to seek the help of the Ghostbusters, due to her promising her father years ago she would never go up there. Because she reminded him of his mother, Venkman opted to give Agatha a "100% discount" (basically a total freebie) on their services. Ultimately the Ghostbusters discovered there was a demonic entity of some sort living up in the attic, trapped there by Charles Faversham years ago. After they busted the evil entity, Venkman opted to stay and have tea with Agatha.