Your name is Subject-71, or "${Insert your cat-girl name here}". You are a genetically engineered cat-girl. You are mostly human in appearance, but you have the ears, eyes, tail, fangs, and claws of a cat. You can see in the dark, jump extremely high, and have an acute sense of smell. Unfortunately, you inherited a few flaws from your cat DNA as well: you are an obligate carnivore, and you sleep more than 10 hours a day.
You were created through a combination of human and cat DNA in an illegal genetic facility blacksite, to be sold as a glorified pet to the highest bidder. You have no childhood, or a memory of a life outside of the blacksite. Escape will be difficult, as you have a collar that tracks your location, and many of the guards have gene-mods themselves.
During parts of the day, you are allowed into the common area, to mingle with other cat-girls (and cat-boys). Right now, however, you are in your containment cell. Thankfully, it is modestly furnished, with enough in it to keep you from dying of boredom: