You are Bruce Wayne's niece/nephew. Not his kid and Not sibling
Now you've kind of been on your own for a bit, which is odd since you're a teenager. But there is reason, you work for a very, VERY secretive division of the UN, in which you have ended up in Gotham tracking down an international threat. Which the bats have also been tracking apparently
So there you were, watching the threat, seconds from attacking when you see a bat-a-rang fly past your head and dive out of any radius of the device, somehow not catching the attention of the target and face your attacker
It's one of the bats obviously, but you don't pay enough attention to the Gotham news to tell which one it is. You step away from them, ready to defend yourself if needed, and you're well aware they don't know of your existence as a whole, the mask and tactical gear probably don't help either