"W-w-what is that!!?" Three squealed all of a sudden.
Taken by surprize, Sam froze for a moment as he climbed onto the bed.
"Hm? You mean…" looking dumbfounded, Sam's eyes slowly went down to his fully erect penis. "Right… this your first time seeing one, huh?"
Valkyries knew nothing about basic biology. They didn't need to, at least not until it was time for them to serve their purpose as artificial wombs. It's only natural for her to be surprised by the sight of something like that.
"This is the male mating organ." Sam said, leaning over the young Valkyrie so their faces would be closer. "Three, do you know where human babies come from?"
"Human… babies?" Three muttered, looking rather confused.
"When a man and a woman who really like each other decide to spend the night alone, they sometimes do something that might result in a child being born."
As he spoke, Sam gently patted Three's head. The young Valkyrie listened carefully, and after a couple of seconds her face went red as she finally understood where this is all was going.
"W-wait! Don't tell me…" looking at him with a nervous smile, Three asked to confirm. "Are we going to…"
"That's right." Sam replied instantly.
"Eh!? B-b-but… I'm not a human! How am I…. Hyaahn!!!"
Noticing how restless she was getting, Sam slid his right hand down her slender figure, stopping at her belly and starting to stroke it slowly in a circular motion.
"Valkyries are made after human females, remember?" Sam said softly. "Don't worry. This will be just a practice run to get you used to the act. We aren't really going to make a baby this time."
"I… see…" Three replied, her eyes locked on the hand crawling down to her honey pot.
Sam took her lips, this time not hesitating to use his tongue. Feeling her mouth being invaded like that was quite the surprise for the young Valkyrie, however with how weak she felt at that moment she had no choice but to submit herself to him and try to enjoy what he's doing to her.
Though they had reproductive organs much like those of a human female, in the end Valkyries are still unable to get pregnant on their own. In order for them to bear a human child they first have to get an egg implanted into them after which it gets inseminated, either naturally or artificially.
Unless an egg is implanted there is no fear of a Valkyrie getting pregnant, which means it's completely fine to have unprotected sex with them as much as he wants without having to worry about the consequences.
Seeing how soaked she had become and unable to wait any longer, Sam let go of Zero Three's lips and began preparing himself.
"Doctor…" Three called, her hazy, barely open eyes following him as he positioned himself between her legs.
"Ah!" She gasped, her hazy mind clearing up a bit.
"Three, this might hurt a little…"
Sam's rod spread Three's slit open, slowly pushing it's way inside. Feeling the stiffness invading her body the young Valkyrie squeezed her eyes shut fighting against the pain, however in the end it proved too much for her, opening them wide as she let her voice out.
She had fought countless Calamities before and sustained numerous injuries, however this is the first time she had felt this kind of pain. She lifted her head to check its source and was immediately shocked by what she saw.
Before she could say another word, Sam went in and sealed her lips, waiting until the initial shock ended.
"Don't worry, Three. It only hurts at first." He said, kissing the corners of her eyes to wipe the tears that began to flow.
Though he was trying to stay calm, Sam was struggling himself feeling his member getting crushed down there. No matter how many times he does it the tightness of a Valkyrie's vagina never ceases to amaze him.
Maybe it's because she looks much younger than the other two but he felt that Zero Three was a little tighter. He fought the urge to start pumping his hips and waited for her to calm down. It was her first time after all, he wanted her to remember it as a pleasant experience.
"How are you feeling, Three?" "Doc… Doctor's… thing… your thing is… it's inside me…"
As he looked down at her, Sam couldn't help but swallow feeling the sweat beading his forehead. That loud, strong and energetic Zero Three was now under him, her face flushed as she panted, looking up at him with hazy eyes.
'Not good…' he thought, reaching out with both hands and grabbing her thin waist. 'I can't resist anymore!'
Holding her in place, Sam slowly pulled his meat pillar out.
"Ah!... wai… aahhn!!!"
Once only the tip was left inside he began pushing, watching carefully as the girl clutched the white sheet making an expression he thought was the cutest so far.
"Three… does it… still hurt?" He asked when he reached her deepest part once more.
The young Valkyrie didn't answered, her quick, labored breaths continuing for a while as she struggled to comprehend what was happening to her.
Unable to wait for her answer, Sam pulled back then pushed in again. He tried his best to keep a slow pace, however with each thrust his patience depleted and soon enough he no longer stopped after going all the way inside.
"Hyahh!... ahh!... hahh… ahh~?…ahh!!... hahh~?"
Pleasure forced his body to move as his rod slid back and forth inside Three's slippery, tight and warm love tunnel. The young Valkyrie cried and moaned, the pain she had felt before having transformed into a pleasant sensation that her body kept asking for.
The faster he moved the stronger the sensation became, however it seemed like she had reached her limit as the heat at the bottom of her stomach moved toward the exit.
"D-doc…tahh~?!! Ahh… ahh~?! Ahhn… hahh…. nHaahh~?!!"
Seeing her hold both hands up at him, Sam leaned in thinking she was asking for a kiss. Three wrapped her arms around his neck and hugged him tightly. Realizing what that meant Sam began thrusting his hips with everything he got causing the young Valkyrie to feel even more pleasure as they came at the same time.
Three's mind went numb as her senses flooded with the strange feeling that spread to every part of her body. She felt herself getting gradually filled with a hot liquid that seemed to be pouring from Sam's member directly inside her and that only served to add to the strong sensation.
As the rush of climaxing began to fade, Three's body relaxed releasing her hold on Sam and allowing him to move. Separating from her for a moment, their eyes met as both of them panted for air and without saying a word they closed their eyes and kissed.
"So, how was it, Three?" Sam asked.
A few minutes have passed already. Though he was still rearing to go Sam decided to allow the young Valkyrie to rest for a while. He helped clean the mess he had made then laid down on his back pulling her toward him and placing her head on his chest.
"Amazing!" Three exclaimed a few minutes later, lifting herself up and turning to look at him with sparkling eyes and flushed cheeks. "At first it was so painful, but then it started to feel really good! And then at the end…"
"I'm glad you've enjoyed it." Sam said, gently patting her head.
Once she had her first time Three seemed to overcome her embarrassment of being so close to him even though they were still naked under the blanket. The new experience filled her with excitement and the smile she flashed him was unlike anything she had showed before telling him of how happy she was right now.
"You do this with Nine and Five all the time, right?" She asked. "No wonder they agreed to become your personal Valkyries!"
"Well, that might be true." Sam said. "Now that you've done it, do you understand what it means to be one?"
Faced with that question, Zero Three looked up at the ceiling taking her time to think of a way to answer.
When she seemed to be ready to respond she looked back at him. The shyness from before returned as she sat down on her knees.
"I think… I think I understand now… yeah…" She kept twiddling her fingers for a few seconds, fidgeting restlessly as she tried to find the courage to speak. "Being with Doctor I always felt safe. I was really happy whenever you held me, and I think it's the same for everyone else."
Listening to her words carefully, Sam slowly lifted himself and sat down as well.
"I never knew it before but… just now I learned that being close to you can make me so happy, even more than being able to swim freely all day." Raising her head and looking into his eyes, Three smiled at him, her chest overflowing with the emotion she felt before. "Doctor, I think I really, really like you!"
Staring at her for a moment, Sam closed his eyes and smiled. His reaction confused the young Valkyrie, however when he leaned in for a kiss she felt that there is nothing to worry about.
"Three, that's called love." Sam said. "Do you want to be my Valkyrie now?"
Not hesitating for a moment, Three threw herself at him and joined their lips causing them both to lose balance and fall.
"Doctor…" opening his eyes, Sam was met with Three's beaming face as she looked down at him. "I love you!"
Saying the three magic words, Zero Three went in and kissed him once more.
Though he hadn't intended on their first time to be a long one, the two of them ended up going at it for the whole night.