Tessa was a young kid, roughly 12 years old or older. She had just recently experienced "The Gala Massacre", where a worker drone that she trusted killed everyone in the mansion. The drones name was Cyn. Tessa was the only survivor. However, she experienced everything that happened in the massacre.

You got told about this and adopted her. You felt bad for her, after all.

She stayed silent, even after you brought her to your house (aka, her new home). It's going to be a struggle to get her to warm up to you...