This scene is killing me. I don’t remember anything else from the movie except for this:

So there is this woman, she’s a fighter, and i think she owns a gun and/or a sword. She dresses up like a goth, or maybe she’s a vampire, I’m not so sure. So anyways, in this scene, she flirts with one of the bad guys and leads him to a room. She then proceeds to push him on a bed, gets on top of him, ties both his hands, then kills him (either by shooting/cutting/biting his throat-vampire style; i don’t remember). She then finds the secret hideout or factory or something where these bunch of kids were huddled up and helped them escape. That’s all the vague info I can remember, since i watched this movie a long time ago. I think it came out somewhere in or between 2005-2007 (no earlier than 2000 atleast). The poster had the lead actress in a red corset, maybe holding two pistols but, again, I could be wrong. Any help would be appreciated :/