She looks like a woman in her late 20s.

It's remarkable actually, I get a distinct feeling she got 50% of her DNA from a human male and 50% from a human female. I can't quite put my finger on what it is that makes me so convinced she is a human. It could be that she appears to be a biped, has two eyes in the middle of her face, a nose, a mouth, seemingly human hair, and her arms end with some kind of extensions that bear a striking resemblance to human hands. Both have five fingers, by the way, not that that proves anything. She also frequently utters sounds that at least to my untrained ears sound very much like human language. Yes, the more I think about it, the more glaringly obvious it becomes: she looks like a woman in her late 20s because she is a woman in her late 20s.