"Dragon Souled," he says, making it come across primly when he's very, very rarely prim at all. "And all you had to do was ask, I'd roar for you anytime."

Literally, it's just a draconic roar, it'd be loud trapped on train, but doable.

"Got it. Why three seconds?" Because he programmed it that way, Jingyi can guess, but he's smirking as he asks, since it is pointedly an insufferably unimportant question.