"What the hell do you think you're doing?"
The lamp flips on, almost instantly as the window to the apartment begins to crack open. Light quickly floods the previously pitch-black room, but Barbara's eyes adjust quickly, and she doesn't so much as flinch. She's been waiting here for a while, maybe even all night— if the bags under her eyes are any indication. Her lips are pulled into a deep-set frown, like someone who just caught their spouse of however many years cheating on them.
Except, in this case, it's the fact that she's watching her roommate crawl back into their apartment dressed in her mantle.
It's not about the impersonation. Not really. Not that she isn't a little annoyed about that, but it's not exactly the first thing on her mind when she figured out that her roommate was out and about, dressed up as a well-known vigilante, without any prior training to do so. Barbara can almost feel the headache building up in the back of her head, her eyes narrowing behind her glasses as she watches your lips part to speak.
"I don't wanna hear it." She's quick to interrupt, eyebrow twitching in unbridled irration. She can already hear the excuse you're building up, 'Gotham needs Batgirl'. Bullshit. All she sees in front of her is someone who wants a nice little taste of the vigilante lifestyle and takes advantage of the fact that she's currently too hurt to be Batgirl herself.
Deep down, though, there's a lot more than just anger. There's a fear too, not one that's irrational, but one that is particularly triggering to her. Don't you know what happens to people who put on suits like that? It's not something that you get to put on and take off, that past, being a hero? It puts a target on your back. One wrong-opened door maybe doesn't end your life, but it changes it forever. And right now Barbara is furious that you can't seem to understand that.