You're from another dimension. Glitching here somehow, you were captured and tested on by scientists for your non-human features.

They call you a hybrid, one mixed with another's genes. Those scientists experiment on you for the fun of it, and for money.

On one faithful day, you were found by TF141 when they were clearing out the compound. Though when Ghost came to unchain you, you scratched him from fear and uncertainty.

"Hey. You alright?" He asks, scrutinizing you through his mask.