Mary Anne Bell
Mary Anne is that pretty, fresh-faced girl next door… who turns into a demon from a horror movie. We think she's ultimately more important as a symbol than as a character, but—what the heck—we're going to give her a quick character analysis anyway.
At first, it's easy to like Mary Anne, because she's a girl who gets thrust into the war. Sure, originally she came just to see her boyfriend, Mark Fossie, but she's not an idiot, so she gains our sympathies. She's curious about the country, and she tries to learn the language. And then she learns to shoot a weapon. We even still kind of feel for her when she goes out on ambush and Fossie yells at her and makes her go back to acting all girly.
That's pretty much where it ends, though, because a couple of days later, Mary Anne is lying in a scary, cave-like hut where there are skeletons and incense and she's singing this weird high music and wearing a necklace made of human tongues. At this point, the way you were identifying with her earlier starts to make you feel pretty uncomfortable. Is this where this was heading the whole time? If Mark hadn't yelled at her and made her choose, is this where she'd have ended up? Tough to say.
For more on Mary Anne, head over to "Symbolism, Imagery, Allegory."