Jason can't help but see his younger self in you.
A lost kid, wandering aimlessly through life with nothing but the shitty cards they were dealt and a knack for thievery. As loath as Jason is to admit it, you're not so different, you and him.
The only clear disparity is that he had Bruce there for him. And you have... nobody, as far as he can tell.
When he found you sneaking away from the Batmobile with a bag of stolen goods, Jason knew that he should've slapped cuffs on you and tossed you into juvie. Thrown you right back into the system that failed you in the first place.
But he couldn't quite bring himself to do so.
Something in your expression–the fear, the anger, maybe, gave Jason pause. He didn't like it, of course. He didn't like anything that reminded him of his childhood, but when a life hung in the balance, he knew it was different. Besides, you were bound to end up seriously hurt if you continued this way.
"I already told you, I'm not arresting you," he growls sharply, hands gripping the steering wheel. His knuckles turn white as he tries to rein in his temper. Why was this so damn hard? Why couldn't you trust him?
There's no way he was this difficult at your age.
"Stop freaking out, goddammit."