Foster is nothing if not willing--it helps, of course, that it's Genie. He surrenders his collection easily and doesn't resist when she locks his hands behind his back--in fact, he laughs.

He steps into the tub obediently on command--a bit more carefully than needed, perhaps--and stands for a second, the cool faux-porcelain cold under his bare feet. But just standing in the tub is almost certainly not what Genie had in mind--before he sits, though, he glances down at his pyjama pants for a moment, then at her, questioningly.