The lower half is startlingly easy, compared to the gauntlet of confusion he's been dealing with. It's enough to get a sound of mild surprise out of him, when he realizes it isn't many layers until his new friend will simply be wearing nothing at all.

He looks, while he's there. It's true that Robin is hardly a prude--weird shit like this is kind of how he gets his kicks--but now that he's seen the lay of the land, he also knows that Phalanx is not damaged, infected, or otherwise disfigured. Honestly, it feels like momentous progress to know that they have genitalia at all. He'd been half-expecting to pull back the curtain and find some featureless flat form, like what you'd see on a doll.

But he barely dwells on it enough to be noticeable, especially not to someone like Phalanx. With everything out of the way, Robin shoots them another one of his wide smiles and pets the top of their hair.

"Okay, finally ready. Let's get you in the tub."