Hypnos didn't bother trying to hid his expression or fighting to keep it off his face. When Iris yawned, Hypnos smirked. It was a little victory, but one he recognized as being a win in his column nonetheless. Lesser gods and goddesses frequently showed their sleepiness in his presence, in various ways ranging from yawns to outright dozing. But he knew that as a messenger for the queen, Iris probably prided herself on being proper.
And he'd made her yawn.
He could, if he chose, reign in his influence. He did it for his family members, and for a handful of acquaintances, with the exception of Thanatos. It never seemed to affect his twin, perhaps an immunity developed in the womb. But Iris? Was most definitely not immune, and Hypnos was feeling perverse enough to simply let himself be as he was. At least for the moment.
It was an interesting request, and Hypnos pondered what prompted this boon from Hera. She didn't give them often, just as she didn't give her favor without cause. In a way, that made her more honorable than some of the other gods who gave favor one day only to take it back the next. Hera was steadfast, as long as those she was honoring were as well. At least with mortals. With gods, she seemed more than happy to use them as she wished.
Not that he was bitter about that. He wasn't. Finding out that she was only being... kind... to him in order to get him to do what she wanted was a blessing in disguise. How many years would he have continued to long for a goddess that was not only out of his reach, but didn't return the affection he held for her? It was a hard lesson learned, but it was better to know.
And now, he wanted to know why this was being asked of him. Because he didn't know that it would be in his best interests to give Hera what she asked for. The first time he'd done that, he'd very nearly become a pile of ash on the receiving end of a lightning bolt. His mother might not be there to save him this time. So he was going to proceed more cautiously.
Though he preferred to remain as he was, happily lying upon a cushioned couch, Hypnos made the effort to stand. Then slowly he made his way toward Iris. When he was near, he flexed his own wings, as he'd just watched her do and smiled drowsy, indolent smile. “Why?”