Xerthe

Xerthe (pronounced Zer-a-thay) She/Her Alien

For plot reasons, I won't list everything here, but she is in charge of running a killing game full of kidnapped humans that are trapped in an apartment that was rocketed to the moon. Her hair is transparent and has an "x-ray"-like quality that can see through most flesh, bone, and her skull; which is something that comes with her race's maturity level, so her little sister does not have the same transparency yet. 

On the outside, she can appear cold and apathetic to the situations around her. The kind of person who always has a coffee in hand, but is always tired