Theresa was a Human Warlock. She was a sword swallower and fire breather in the carnival.

In Vilchya's lair, Theresa ate the white apple from the Gulthias Tree and was immediately killed. The party took her body to Barovia and had her buried.

Theresa's Background

I come from a poor family. My mother was my hero who taught me card and dice tricks, and I'm sure my father was good deep down, but the demon who possessed him had other plans. After my father killed my mother I ran away, leaving my older brother to take care of my younger sister, and I never saw any of them again. I was 12.

I wandered Ravenloft begging, performing the few childish tricks mother taught me at taverns and street corners, and sometimes my audience gave enough to fill my belly for the night. Eventually I met some traveling magicians who didn't think twice about teaching an innocent little girl magic tricks for free. I soon learned I could even get tavern-goers to pay for whole meals, just for the promise of showing them how I did my tricks. 

There were days I never ate at all, sure, but my luck changed when I met Urgon Eater Of Fire. The great magician taught me how to swallow flames as large as barrels of ale, though all you were doing was putting it out in your mouth. It took me a while to learn, while practicing I slipped and had burned half my hair almost to the scalp. That was alright, though, I made up a story of my family's house burning down, and it drew more pity, and coin, from the townsfolk I begged from.

Having learned more and more street scams I soon grew more ambitious and, against my better judgment, scammed a money-hungry lord out of more than 20 gold pieces, more than I'd ever dreamt of having. But I dropped it all while running from the lord's henchmen.

Outside Ravenloft was no place to make a living as a hustler, even a hapless child hustler. The taverns are too spread out and scarce. But I did find a sort of... temple. Having no place else to go, I entered it planning to offer my services, and to worship whatever god they worshipped. 

I still don't know whether the Elder Being had meant for me to arrive that day, all I know is that from that day I would forever be one of his countless loyal subjects.

Over time the cult I had joined taught me how to communicate with the Elder Being. He spoke to me through my everyday thoughts, and my dreams. His voice was other-worldly and alien, but somehow soothing. I welcomed it when it came, it filled me with a strange happiness. But the cult warned me not to listen too often, or he might decide to claim my mind for his own. 

Thankfully I obtained only wisdom from the Elder Being, not insanity. He gave me a path to follow that would keep me safe, and I gladly took it. I would have to find a band of travelers, he said, so as not to stay in the same place for long. Any traveling group would do, but which one? Sitting in the church contemplating the candles across the pentagram, my mind wandered aimlessly back to one of my earliest memories, when I was about 7 years old and a traveling group of entertainers visited my neighborhood. What a great escape from my pitiful childhood, to watch them perform.

That was what led me to join a circus, and eventually wind up with Argyle Wellington's Wonderarium of Confounding Curiosities, where I would lend my skills as a fire-eater and sword swallower. The fire eating I learned a while back as a hustler. The sword swallowing I learned as a warlock, from the Elder Being.

But I must keep the identity of my patron a secret, he said, and the most important thing: I must not reveal my true identity until such a time came when it was safe to do so. I assumed that meant that the greedy lord from all those years ago was still searching for me. But the Elder Being only tells as much as you need to know. So, to my fellow performers, I am Theresa the Eater of Fire and Swords. To myself, and to the Elder Being from whom no truth is hidden, I will always be Matilda, the poor runaway girl-turned-hustler from Ravenloft.