A/N: "Uwa" is a sound Japanese people make when they are surprised.

"And remember class, always practise safe sex. You don't need to be forced into anything. It is ok to say "No". Please remember my assignment on the female reproductive system is due next week. No late submissions." And with that Miss Kaede ended her Biology class. A confused Yuki walked out of her class to see her sister waiting for her.

"You came Kana-chan. But don't you have late classes today?"

"Not today. Since I submitted my pieces on time, sensei let me leave early."

"Yay! So I get to be with my Kana-chan for the whole afternoon."

"Yes. It is good you stopped working. I mean we can manage somehow by careful spending and saving too, right Yuki-chan?"

"Hai."

I know about the birds and the bees and how it happens between a man and a woman but how does it happen between girls. Why am I feeling this weird sensation down there? It is probably from all the sex talk in Biology class. Learning about the reproductive system is important but I don't know how it relates to me. It's not like I'm planning on getting pregnant or anything. I guess I could understand it more if I actually feel the real thing. They say it's what lovers do. Are Kana and I…?

Yukino's head was spinning like a motor. Her biology class made her question sex. They had taught her about safe sex and reproduction before but she had never given much thought about it. Now more than ever, she was closer to her sister. They were almost like lovers. It dawned on her that it was only natural for lovers to sleep with each other.

The conversation between her and her sister was dull as they walked to their dorms. Yuki was hoping that her sister hadn't caught her reddened cheeks as a million thoughts flooded her brain.

When they entered their dorm and closed the door behind them Kana got the shock of her life when her sister bluntly asked her "Kana-chan, have you ever had sex?"

There was a pause. A long one, that is. The silence between the Sakurai sisters was heavy. Kanade felt her heart skip a beat at that question. She thought for a 16 year old girl, sex was nothing to be ashamed about. However discussing this particular topic with her sister just felt…wrong or at least it should feel that way. So then what could explain the pounding of her heart at the word "sex" coming out of her sister's mouth?

She cleared her mind and answered honestly, "No, Yuki."

Yuki was quick to respond. "Me neither. I mean I know what it is but today we discussed the reproductive system in depth and it just got me thinking." She paused and exhaled. "I know it is what lovers do or supposed to do but I was only taught about it being between a man and a woman."

Kana's pupils, now dilated, stared at the desk as her sister spoke for she was unable to look her sister in the eye.

"But I don't know why we never learned about what happens between a girl and a girl. Kana, you and I, we are…" She swallowed as she choked on her words.

"We're lovers. That's what you want to say right?"

"Hai Kana-chan."

Suddenly she felt a weird metallic taste in her mouth.

"Uwa Yuki-chan. Your nose. It's bleeding. Here take my handkerchief."

"Kana-chan! You're bleeding too!"

Yukino was incredibly overwhelmed with embarrassment as she remembered the time this had happened to her when her sister was giving her a sponge bath. But that's when she was sick and could have come up with an excuse, an unbelievable yet passable one. However she was strong and healthy today and the weather was fine.

I can't believe it. Both of us are bleeding through our noses. Sensei did say something about this happening when the blood has to go to somewhere while the body was aroused; that is, through the nose. Does this mean that Kana is also getting that weird throbbing down there too?

Both sisters' cheeks were on fire as they wiped the blood dripping from their noses.

Yuki changed the subject. "Wow. It's getting so late already. Time to get started on that algebra homework."

"Come here baka." And before she knew it, Kanade Sakurai's arms were snaked around her waist. She pulled the blonde closer to her body. She felt Kana's warm soft lips on hers. At first, the kiss was small. But then it grew bigger, and more intense. It was probably the most intense kiss they had ever exchanged.

Kana felt Yuki's moist tongue pushing against her own as her head was slightly tilted and her eyes closed, as she accepted every dose of passion from her twin. Everything about Yuki was intoxicating. From her scent like chocolate, to her slender physique. That chocolate fragrant of Yuki was like Kana's drug, her own personal brand of heroin. Her sister was truly a gift from the heavens she thought. She had always admired Yuki's Coke bottle-shaped body from afar as she waited for her at swim club. People normally find the love of their life to be perfect in every way and Kana thought of Yuki no less.

Without any thoughts or worries the lovers fell on the bed, their tongues still connected with Kana on top of Yuki's body.

Yuki finally broke the kiss to speak. "Kana I've been feeling weird down there. You know like how you feel your heart beating but it is not my heart that is beating. It happened today when we were discussing reproduction in Biology class. I don't know what it was. Now it is happening again."

Kana was surprised for she had been feeling the same way too. "Yuki I…so why are you telling me this?"

She nervously giggled. "Well you see Kana. Funny story. In one of those dirty mangas I caught Sakuya reading, the girl had her boyfriend rub her here…" and with a swift motion she pointed to her vagina "…and well I thought that maybe you could…" She swallowed as Kana glared at her with dark lust-filled pupils. "…you know."

Kana's heart quickened. She thought the whole building could have heard her swallow her saliva when Yuki had finished speaking.

"So you want me to…touch you? I have never. I mean we have never done this. I don't know what to do."

Yuki unbuttoned the skirt she was wearing and slid it off with her lily white panties too. Her most tender part was exposed to the one and only person she felt it belonged to. Kanade helped her sister undress by taking off her school shirt. Kana also took off her shirt but left her skirt on because she was shy. They had no experience, not even from themselves, for what was about to follow. Kana shuddered at the thought of what she was about to do to her sister.

I know it is what lovers do.

Those words her Yuki-chan said were on loop in her head like a broken record.

We declared our love for each other and someday we have to do this if we truly believe we are lovers. I have to do what she asks. It's only natural for us to feel this way.

"Please Kana-chan, don't make me wait."

Kana slowly began to brush her right index finger on Yuki's opening.

"A little more up, Kana."

Kana did as she was told. She lightly brushed her index over her sister's pink bud.

"Ah. Your fingers are so cold. Don't be scared Kana."

Kana's eyes were three times as wide as she began to shiver with fear of hurting her sister. "Uwa! Did I hurt you Yuki-chan? I'm so sorry. I'll be more careful."

"N-no. You didn't. You are a bit nervous but it is okay. Keep doing the same Kana-chan. It feels good."

"Oh ok if you wish."

Yuki felt Kana's inexperienced finger on her love bud again, this time moving a little faster with swifter up and down motions.

"Ohhh Kana." Yuki moaned. "Please. Try two fingers now. I want to see how it feels with two."

She felt her sister apply pressure with both her index and middle fingers working simultaneously to pleasure her. Her gentle touch made Yuki's body quiver as a wave of euphoria overcame her. The only thing that she could focus on now was the feeling of her sister's circular motions on her love bud.

She's learning so fast. She's so good at this for someone who never did this. How can our love be seen as "wrong" when this feels so right?

Unconsciously, Yuki was massaging her own breasts. She lost her senses as her sister picked up her rhythm.

Kana glanced at the constricted facial expression on her sister's face. Her eyes were closed and her mouth was opened as soft moans escaped in her breath.

"Yukino, is this ok? Should I go slower? Don't be afraid to tell me if I am hurting you. I won't scold you if you tell me. I promise."

I hope I am not hurting her. I have never done this before. She's my sister, my lover. The last thing I would want to do is hurt her

"Kana I'm going to…"

And with that Kana felt a hot sticky whitish liquid on her fingers. She gasped as she remembered this was the same liquid she saw on her sister as she was giving her a sponge bath.

When Yuki's body had done convulsing with orgasm, she said "Ahh that felt amazing. Maybe I should do this to you too Kana. Thank you Kana-chan. I don't care how much you hear this from me but you truly are the best sister in the world."

"Yeah, maybe some other day you will return the favour Yuki-chan." she responded with a warm smile. Kana was pleased that she had done a great job. Once her lover was pleased, she was. However part of her wished that Yuki would do the same for her. Even though she had offered, she declined. She admitted to herself it was because she was waiting for the right moment. She thought that today, it was Yuki who felt like she was in the right moment but Kana was cautious. She hated to rush things. She wanted her sister but she wanted to wait. After all they did have each other to themselves. They belonged to each other like a missing puzzle piece to the rest of the puzzle. Both sisters carried that piece and when both pieces were brought together, a deeper love was found. They completed each other like the moon completed the day.