Byakuya tried his best to not show his surprise and amazement by not letting his mouth hang open. Yachiru put on her best behavior, cautiously minding her manners and thoroughly impressing his elders. Though she refused to let herself be roped into anything too domestic, she was pleasant and courteous, even biting her tongue on a few occasions when the 'old farts', as she fondly referred to them later, made snide remarks and crude critiques poorly disguised as compliments.
Yachiru dressed in a lovely black kimono with pink cherry blossoms on it ("Because they remind me of you," she told Byakuya, batting her lashes playfully) and spent time and effort styling her hair. She checked her baggage at the door, as Byakuya had heard Rukia refer to it once, and put on her game face.
The only drawback, naturally, was that he made a promise to his parents, or rather to his parents' gravestones, that he would not marry someone who was not of noble lineage, and the elders were also set on holding him to such a premise. So, after their official engagement dinner with his family, Yachiru wandered off to the koi pond for some fresh air and Byakuya escaped to his parents' burial plot. And that is where Yachiru found him some time later, he engaged in very deep thought and she observing silently from a distance.
As Yachiru approached him she considered what he might be thinking and quickly decided on a rebuttal. Byakuya sensed her approach and stood, smiling, as she walked up to him. Her slender frame and womanly figure defined perfectly by the light of the now setting sun rendered him speechless for only a moment before he reached out his hand to her and she grasped it lightly. "Ah, Yachiru, I thought you might be looking for me by now. Come with me?" Byakuya asked, leading Yachiru back to the manor through the gardens to one of his favorite, secluded spots.
"Byakuya, what were you doing out there by yourself? Talking to dead people again?" Yachiru quipped, then looked suddenly abashed as though she felt she might have upset him. But Byakuya did something people claimed he was incapable of doing and laughed softly.
"I suppose, yes, I was. More for my own peace of mind than anything, really. I was just apologizing for breaking my promise again. But, I suppose your are correct, they are deceased, gone on to the cycle of reincarnation. It does seem somewhat superstitious to continue honoring them as I have tried to do. My mother could have been one of the Arrancar, what with her temperament when I angered her. Old habits die hard." Byakuya continued on his train of thought for a while as Yachiru listened intently to his ramblings. (1)
Byakuya paused for a long, deep breath. He looked at Yachiru standing on the other side of a small bridge as her hair glistened in the moonlight, the sun's final rays now completely gone. "What I mean is that I am willing and happy to accept the consequences of my actions in this endeavor, traditions be damned."
Yachiru said nothing and instead wrapped her arms around Byakuya in a warm hug. She kissed him gently on the cheek and backed away an arm's length. She inhaled deeply as she smiled and softly said, "Thank you." Byakuya returned her smile and swiftly captured her lips in a deep kiss.
He began running his hands through her hair, tugging gently at the strands, and placed a hand on her stomach, just beneath her breasts. With the touch of butterflies' feet he graced her sides and stomach, moving up slowly toward her neck, touching only the slightest to her breasts, leaving her weak in the knees and trying to subtly coerce his hand to where his touch would be more desirable. Byakuya would have no persuasion and continued on his planned track to drive Yachiru to the edge and not let her go over it. His touches grew steadily heavier as she started moaning lustfully.
Yachiru attempted to redirect Byakuya's touches toward her nipples, and he slowly decided to follow her lead. She let out a small squeak of pleasure as even through the fabric of her kimono Byakuya's fingers made her nipples perk up. He continued with his massaging, even managing to keep her mouth occupied with his while one hand slipped beneath her kimono to touch her bare chest. Yachiru attempted to return the pleasing sensations to Byakuya, but ended up spending most of her efforts simply standing upright.
"Maybe… we should… get to a bed somewhere… Byakushi?" Yachiru rasped out.
Byakuya ignored her for some time, carrying on with his plan. When he decided to acknowledge her, he spoke simply. "Perhaps. But I do have further matters to attend to with the family elders. I believe they were expecting me just after sunset. I need to be going."
Byakuya kissed Yachiru a final time on the cheek and briskly walked away, waiting until he heard her growls and yells of frustration before he grinned widely and made his way to his quarters to retire for the night.
(1) – I am actually not 100% sure that's what all the promises and apologies and what have you were about.