Normally, Romulus probably wouldn't have reacted to Elitia's state of dress. He'd been around naked girls for it to not faze him.
Alternatively, he might have been very affected by it, and they may have gone for it at some other time.
But as it was now, he was in pain and tired and a bit addle-brained. He was sitting on the edge of his bed in nothing but a pair of shorts, working on not falling over as Lear figured out his clothing. The sight of a beautiful woman entering his room, wet-haired and largely naked, flicked all his switches, but his body hurt too much to respond. He also didn't have the brain power to control his reaction very well, and so he wound up just staring at her in open appreciation, with a dopey-looking smile on his face.
The Prince didn't even realized he'd been asked a question, until long after the fact. "Hmm? Oh, I'm alright." His voice was still trying to wake up, rumbly and low and groggy.
Lear almost snickered at him from across the room. Romulus could be such a boy sometimes, for a man carrying all the weight he carried. Pretty girls still do the trick.
"Elia, I laid out your dress on the bed back in my room. Didn't want to interrupt your bath but it's in there." She wouldn't have necessarily seen it unless she was looking for it. He walked over to the Prince with a couple of soft-looking knitted garments, done in the typical royal red and black. He was always aware of how big Romulus was, but every time he helped the Prince pick clothing, he was reminded. The sweater he'd chosen was big enough to fit 2 people his size, or likely 3 people of Elia's build, and Romulus would fill it out nicely.