He can't, of course, read minds; those who fear replicants the most think they can but that doesn't make it true. He can see that Jesus likes this. He can see that the way anticipation is threading through his expression - not yet rooted into place, but familiar - means he's considering more, and likes that too.

And he can read the mischief every bit as loud as the pleasure, as the cool tones of relief. So no, he can't tell exactly what's behind the lift of the brow but he turns his hand up without lifting it, offering it, and what he says is, "It's okay."