With Project X Zone's US release weeks away, I decided to try out the demo while I wait for the game to arrive in the mail. Long story short, the boss for "Demo A" (no idea why it's named that way) is "Aya-me" from the Sakura Wars series. Despite my lack of information on the series, the game was nice enough to provide just enough dialog between characters to inform players that:
a.) She was one of the "good guys" at some point.
b.) She's died at least twice, possibly within their series' universe.
It's very doubtful that any form of on-screen EC will happen in this game, though you should probably look into it if you have a 3DS and you're looking for something...different to add to your game library. As I said before, there's a demo available now; you can find it in the eShop.
As consolation for everyone else, here's a clip of Ayame Fujieda's EC into "Aya-me" that I stumbled across while I was trying to find more information on the character: