Homura looks a little surprised by the sudden arrival of one of the more senior members of the Agency, and her sudden recruitment.  After a few gestures to confirm Aki meant her, she starts with the questions.  "What are the details," she asks.  It's the best start.  "I'm happy to help, but I'd like to know what I'm getting into, at least."  

Part of her also just wanted to ask "Why me?" but she thought better of it.  That could happen later.  As it was, she'd just been drafted for something urgent, and it wasn't what she originally planned, but as long as she wouldn't be in way over her head, there should be a problem.  Shame she didn't know what she'd just agreed to, yet.