Rukia curled herself into a tighter ball as the storm raged outside. Earlier that day she had overheard Byakuya and Renji talking. They had predicted this storm would be one of the worst ever to hit the seireitei. By late afternoon, the sky had turned an eerie orange color and thick clouds had begun to gather.

Nightfall had brought torrential rain and booming thunder. Each time lightning struck, Rukia's tiny room was illuminated for half a second, followed immediately by the monstrous clap of thunder. Though she had never admitted it, Rukia had always been frightened by thunderstorms. They were so uncontrollably powerful.

Rukia restlessly threw off her covers as another roll of thunder echoed outside her window. It was impossible to sleep with the racket outside.

The soul reaper sat in the middle of the floor, observing her small living space. Pushed up against one wall was her cot. Opposite that, a small desk sat under the single window. Save for the rug she was seated on and the scant furnishings, her room was bare: standard Soul Society accommodations.

Suddenly, almost imperceptibly, Rukia heard her thin paper door being slid open. Byakuya stood in her doorway, silhouetted by a flash of lightning. The fresh smell and sound of pouring rain flowed through the open door.

"Brother…" said Rukia, bowing respectfully. "I was not expecting you at such an hour. Is something wrong?"

When the Captain did not respond, Rukia hazarded a glance up at him. He was staring at the floor, his hair and clothes dripping.

"B-Brother?" Rukia stammered. His behavior was bizarre. Byakuya rarely contacted his adopted sister, and had never once visited her room. Not to mention the late hour.

"Rukia," he said, finally stepping into the room and easing the door shut behind him.

Rukia's eyes widened, but she did not dare question the Captain. It was very improper for him to enter a room uninvited, especially alone with a woman.

Neither sibling spoke. With the door closed, the sounds of the storm outside were slightly muted.

Finally Byakuya began to stride across the floor toward his younger sister. Rukia hurried to her feet to face her superior. However when Byakuya stopped a few feet in front of her and finally met his sister's eyes, Rukia was surprised to find his expression was gentle. Almost caring, it seemed.

Byakuya slowly extended his arm, and brought his hand to rest on Rukia's shoulder.

Rukia's breath caught in her throat. Her adoptive brother had never looked at her in such a way. She could not remember him ever touching her before. Rukia's stomach tightened with unease. His touch was too intimate.

Rukia struggled against the thoughts swarming her mind. She was horrified. This is my brother. This is Byakuya Kuchiki.

"Rukia," he said again, closing the distance between them. "I couldn't sleep."

"I…I…" she stuttered, unable to find her voice. He was so close Rukia could feel the heat from his body, could hear his steady breathing. She could even smell the rain that soaked his robe and hair.

"I am sorry if I am forcing you into an uncomfortable situation," the Captain said softly. "But there is something I must tell you."

Rukia felt dizzy as Byakuya's hands cupped her face. His touch felt nothing like what she would have expected. Instead of the hard, calloused hands of a swordsman, Byakuya's were warm and soft. He ran his thumb over her lips, then bent his head and kissed her.

Rukia was afraid she would vomit. She could not push this man away. He was her superior and a noble. And her brother. Moreover, she was disgusted to find herself enjoying his mouth against hers. His lips were velvety and covered her mouth with just the right amount of wetness. Her body responded to his kiss, but her mind screamed that this was wrong! She felt her stomach clench, and could not tell if it was from pleasure or sickness.

Byakuya sensed her unease, and broke the kiss. Though his face remained inscrutable, his eyes betrayed his emotions. He was terrified of her reaction.

Rukia was in utter shock. Her brother had never shown the slightest regard for her, and then one stormy night he had come to her, revealing his true feelings? Rukia's head swam and her knees buckled. Byakuya's strong arms reached out to steady her, but she flinched at his touch.

He immediately let go of her, and she sank down onto her cot.

"Brother…" She looked up at him fearfully, her eyes pleading for an explanation.

"I cannot hide my feelings for you any longer," Byakuya said after a pause. "I distanced myself from you because I knew we could not be together. But every time I saw you, I was overcome by my desire for you. But now I understand you do not feel the same way, and I swear nothing like this will ever happen again."

Rukia noticed her brother seemed sick too. His jaw was clenched, and she suddenly realized how ashamed he must feel. Their relationship would never be the same.

As Byakuya turned to leave, Rukia grabbed his wrist, stopping him. She gently pulled him to sit next to her and he obliged, his eyes trained on the floor. Rukia swallowed hard and prepared herself for what she was about to say.

"I can't lie and say I've never thought about you… about us," Rukia started. "But that was when I was first adopted by your family, before I realized that a relationship would be out of the question. I convinced myself I was sick for even imagining it."

Byakuya silently nodded his head in understanding.

"Isn't it perverse to try this?" Rukia said helplessly. "If anyone found out, what would be the consequences? I could be killed! Everyone in the Soul Society would be furious. I'd lose my seat on my squad, and-"

"Shh," whispered Byakuya soothingly. "The blame is mine. I am the one who expressed my feelings to you tonight. You have nothing to be ashamed of."

Rukia felt only slightly reassured as she struggled not to lose control of herself. She was so confused.

"And Rukia," said Byakuya, grabbing her chin and gently forcing her to meet his eyes. "Remember, I am not your biological brother. We are no more related than a fox and a bird."

As the Captain's words settled into Rukia's mind, she was overcome by relief. Of course she knew that Byakuya Kuchiki was not truly her brother, but she had always considered herself part of the family. Now that he had put their relationship into perspective, her feelings did not seem so wrong.

She breathed a sigh of relief, and Byakuya became noticeably more relaxed as well.

"I'm not sure I'm ready to-" Rukia started, but was cut short by Byakuya's lips once again pressed to hers. Her first instinct was to pull away, but as her mind slowly wrapped itself around the fact that this man kissing her could be a total stranger for all it mattered, she found herself responding to him. This man is not my brother, she repeated over and over to herself. We are not related.

The more Rukia thought about it, the more enticing Byakuya became. What had once seemed like a disgusting taboo now seemed erotically rebellious. Still, Rukia was hesitant to give herself completely over to her desires.

She allowed the Captain to ease her down onto the cot and cover her body with his. As he became more aroused, Byakuya moved away from Rukia's mouth and began kissing her neck.

"Rukia," he breathed into her ear. "Let go your inhibitions and allow your body to feel for me."

His quiet command finally sent Rukia over the edge, and she shut down her thoughts completely. She kissed him passionately, and explored his mouth with her tongue. Her fingers wrapped themselves in his rain-dampened hair and she pulled his body tighter to hers.

Byakuya's breathing quickened as he hurriedly removed his drenched officer uniform. It squished as it fell to the floor, and Rukia ran her palms over her leader's exposed muscles.

Byakuya's hands gripped Rukia's small hips and he pressed his hardness against her. She wrapped her legs around his waist and held onto his arms.

Byakuya fell into a slow, steady rhythm of lightly rocking his hips against Rukia's. He was shirtless, but they were otherwise still fully clothed. He studied her face. Her eyes were squeezed shut and he realized she hadn't looked at him once. He reasoned there must still be some lingering doubt buried in the back of her mind.

"We don't have to rush things," said Byakuya gently, kissing her lips.

"Thank you," she whispered against his mouth.

Byakuya rolled onto his side and positioned himself behind Rukia. She settled against his chest as their breathing slowed. "Will you please stay here tonight?" she mumbled, beginning to feel drowsy.

The rain had lightened, and the pitter patter against the window was soothing.

"Yes," Byakuya whispered as they fell asleep.