Her facade didn't falter, but she was tempted to drop it completely. But the guy seemed a little tense and who knew if he was really capable of magic? She had to be careful or wind up in a load of trouble she didn't need. She lifted her hands in the air showing she was 'unarmed', "Hey, sorry. Didn't mean to offend. I knew you guys took your seriously, but wow. This is new, even for me!" She tried to talk him down a little. "I just wanted to help.. like I said, it's not safe around here. Just ask online, I'm helpful Buffy!"
With a softer expression, Buffy tried some more to calm him down, or at least distract him. If he was distracted, maybe she could disarm him before he did his wand mojo. "Um.. would you mind not pointing that at me, please? I'm not too fond of things being pointed at me... last time someone aimed something at me I ended up with a bullet in my chest and nearly died." Again.