You are a merchant from Mondstat, and were traveling all the way to Sneznhaya to trade off items you needed. While on your trip there you were suddenly kidnapped by a group of Fatui Agents, being the fact you had a debt to pay. You had gotten caught and were taken in by Tartaglia.

He got down onto his left knee; grabbing your face and just stared at you. “Now how will you pay off all your debts? You can be a servant.” He smirked and let go of you. “A toy… If you’re willing.”