He finds them out around the east wing of the house, shoji screens flung open to admit the warm evening air and a sweeping view of the shadowy garden. They don't seem to notice him out on the path, enjoying a quiet walk in this welcome window of free time, and so he lingers, watching the way Rukia's head dips down to rest against Renji's shoulder - comfortable, familiar, a display of easy affection facilitated by the liberal consumption of sake. Sake scavenged from his own supply, going by what he can make out of the bottle's label. At least it is going to better use than that to which he would put it, a dull, ceremonial offering in the company of dull, ceremonial people.
Renji and Rukia certainly do not stand on ceremony - they appear to have dispensed with the formality of cups, preferring to pass the bottle back and forth between themselves as they talk in thick, slurred voices. He is too far away to hear what they are saying, and in truth he prefers it that way. There is a friendly intimacy between them that he loathes the thought of imposing upon, and he is ready to turn away, to redirect his own steps so as not to interrupt them, when they look up and catch sight of him at last.
The change is instantaneous.
"Taichou!"
"Nii-sama!"
Hopelessly unsteady on their feet, nonetheless they rush out to the path and make an attempt of the proper deference, and one corner of his mouth quirks ever so slightly as he watches them stumble into one another and very nearly fall. It is Renji who manages to salvage his sense of balance first, catching Rukia with a clumsy arm so that she, too, settles back more steadily on her own feet.
"Enjoying the evening, Sir?" asks Renji, and beneath the liquid courage there is a desperately awkward note to his voice - they so rarely speak outside of the office, and they certainly never cross paths here, after hours, in the stately manor with its sprawling gardens that Byakuya calls home. Still, he is as earnest and eager as ever, and Byakuya indulges the question with a graceful nod of his head.
"It is peaceful," he observes, "and warm. Summer is nearly upon us."
"Such a shame to see the gardens wilt," says Rukia, and it is to her credit that only the faintest shadow of a slur mars her speech.
Renji nudges her with an elbow, then realises his mistake and lurches to catch her again as she tips sideways. "Er...I'm looking forward to some nice hot weather for once," he says sheepishly. "Then again, I may feel differently once I'm out leading training drills at high noon, eh, Sir?"
"Perhaps." There it is again, the amused quirk at the corners of his lips, and he turns his face aside to keep the reaction private. He needn't have bothered, really; Renji's gaze is fixed on a point several inches to the left of his head, and Rukia is looking him squarely in the shoulder, and both of them are apparently under the impression that they are facing him properly. He is beginning to suspect that replenishing his cellar in the wake of their raid will cost him more than the price of the two or three bottles he'd initially assumed.
"Would you like to join us, Nii-sama?" The request is heartfelt, although her eyes tremble with apprehension that she probably could not have overcome without the aid of liquor. Still, how things have improved between them, these late spring days, that she can stand before him and ask for his company with no true fear, no shame, but only the anxiety of one who fears that her own company will prove inadequate.
One day, he thinks, he will set aside the time to sit down with her and talk, in warm and open tones, and learn the thousand trivialities that clutter her heart now that the bitter strain of the battle against Aizen has fallen from her shoulders.
Tonight is not that night, though. Tonight, Rukia and Renji are giddy and carefree and weightless, and Byakuya has seen enough of life that he knows the value of weightlessness. Knows better than to mire them down with his own ingrained solemnity - and in any case, they surely cannot expect him to drink straight from the bottle as they are doing, and they have nothing else to offer him.
"I fear I still have work to attend to," he says gently, and he begrudges them neither the disappointment nor the relief that they are too inebriated to keep from their faces. It is a lie, of course - he has long since acquitted himself of the day's duties - but it seems simpler than any other explanation he has to offer them.
There's only the slightest twinge of regret as he takes his leave - a soft , existential melancholy brought on by the swaying of the trees in the night breeze and the glimmer of starlight overhead, that tells him they could vanish tomorrow and he'd never have spoken a sincere, unguarded word to either of them.
He shakes it off - how maudlin - and as he turns the corner out of sight he can hear the muted sounds of their renewed conversation behind him.
And he thinks that they sound happy.