|Via Anime Characters Database|
And yep, it's definitely a kid.
Well, not totally. Cynthia, the above portrayed child, is actually a boomer, who is directly connected to a powerful orbital laser system that can destroy a pretty big area; we're talking several square miles. But what makes her death so sad is that Priss had connected with the little girl while she attempted to "rescue" her (well, before she found out that Cynthia was not human) and that, despite the fact that she's a machine, she shows real emotion. In particular? Fear.
Genom activates the laser system and pinpoints exactly where Cynthia is, an area of Tokyo that seems to have been abandoned after the earthquake (Aqua City), and as the beam comes at her, she screams for Priss. It's truly heart-wrenching, actually; the voice actress does such a good job of infusing desperation into the little girl. I mean, it's totally a kill-the-puppy situation, where Genom plays the role of Completely Awful Bad Guy by murdering an innocent, but hell, it's effective. While I teared up when Priss mercy-killed Sylvie, I actually for-real cried when Cynthia died. Good job, Youmex. I guess?