"I will do everything I can to help you become the King of Britannia."
The moment Shirou said that with a serious expression, Morgan's eyes widened.
She was a half-blood, born of a fairy and a human, and had possessed [Fairy Eyes] since birth, eyes that could see through lies and reflect the truth.
And even among half-bloods, Morgan was exceptional to an unprecedented degree.
Her power rivaled that of the pure-blooded fairies of the Inner Sea of the Planet, and her [Fairy Eyes] were also ranked at the highest A level.
"So it doesn't seem to be a lie. You really do want me to inherit the throne..."
Morgan fell silent for a moment, then let out a sigh.
"Let me ask you this first. Why do you think that?
Is Teacher Merlin's training too harsh?
Or is my dear little brother simply a coward who is afraid to bear the burden of becoming king?"
Under the witch's mocking gaze, Shirou answered solemnly.
"I want Morgan-nee-san to be happy."
"...Huh?"
"I just want Morgan-nee-san to live a happy life. That's all."
This was already Shirou's second transmigration.
First, he had been sent into the Type-Moon world by a truck and taken the place of the Shirou of that world.
Then, before the Fourth Holy Grail War had even begun, he had somehow been thrown another 1,500 years into the past.
After realizing he had arrived in fifth-century Britannia, Shirou came up with an idea.
He decided to do what all those fanfics from his previous life did and give Artoria and Morgan happy lives.
After all, the essence of fanfiction was making up for regrets.
Having read countless web novels, Shirou had a thousand ways to break the deadlock. But just as he was getting ready to make his grand move...
Merlin, you bastard. You actually erased the Artoria route!
With the heroine of this era, Artoria, no longer going to be born, there was only one thing left for Shirou to do.
"Morgan-nee-san, please allow me to offer you my loyalty."
Shirou clasped his foster sister's hand tightly and said in all seriousness,
"I'll stake everything I have on making you happy."
"........."
Morgan's pupils trembled. With her lips half parted, she murmured,
"Do you... even realize what you're saying?"
"I do. I know very well, and I'm perfectly clear-headed."
"Why..."
Morgan stared at the sincere boy in front of her, utterly shaken.
Why are you so fixated on making me happy? So much so that you would even give up the throne of Britannia?
No, actually, that was not the real question at all.
If a man wants to make a woman happy, then even a child knows there is only one possible reason.
Shirou had fallen in love with Morgan. That was all there was to it.
"What's wrong, Morgan-nee-san? Your face is really red."
"Ugh..."
Morgan pressed her lips together shyly and shot Shirou a resentful glance.
Of course, this was not the first time Morgan had felt goodwill from the opposite sex.
Ever since she had just begun to grow into a young woman, the men around her had already been unable to hide the desire in their eyes.
Whenever men openly fawned over her, Morgan had only ever found it disgusting.
But this time, Shirou's straightforward confession did not make her feel sick. Instead, it stirred up a strange feeling she had never experienced before.
Her cheeks burned, her heart raced, and everything above her neck and below her knees felt light and unsteady...
Ugh... what is this infuriating feeling that's throwing my heart into chaos!?
"W... we're brother and sister, aren't we?" Morgan muttered shyly through clenched lips.
"?"
Shirou had no idea why she was bringing that up. He wanted to put her on the throne of Britannia, so what did being siblings have to do with anything?
"We're not actually related by blood anyway."
"Ugh...!?"
Morgan thought to herself, This child may look cute, but inside, he's even more... than I imagined.
Even if they were not blood-related, did that really mean siblings could be together?
"Father and Teacher would never approve!"
"This is our business. It's not Uther and Merlin's place to point fingers."
Shirou looked completely at ease. Once Uther died, he would simply hand over the throne he inherited to Morgan. Was the man supposed to crawl out of his grave and object?
"Y... you really are..."
Hearing him say that, even the tips of Morgan's ears turned bright red.
Shirou, do you really want to be with me that badly!?
Mortified and flustered, Morgan suddenly grabbed a nearby pillow and chased Shirou out of her bedchamber.
...
...
After that, Shirou continued studying under Merlin.
At the age of ten, he became an Apprentice Knight.
From then on, Shirou often left the palace and set out on adventures under a false name.
He grew quickly, especially in swordsmanship.
Perhaps he had always possessed that talent.
Considering Archer's level of skill, Shirou's ceiling in swordsmanship should have been second only to Lancelot's, perhaps even enough to earn him a place among the Knights of the Round Table.
By the age of thirteen, there were already not many adult knights in Britannia who could defeat Shirou.
Aside from swordsmanship, Shirou's other great strength was his Projection Magecraft.
As a transmigrator, he could project all sorts of swords he had known from various works in his previous life.
[Blades of Chaos], [Yamato], [Aegis], and so on.
And this was not just a copy of their appearance. As long as Shirou poured in the corresponding magical energy, he could bring out their original performance and special abilities.
Shirou suspected this was his cheat as a transmigrator.
Unfortunately, Shirou's ability, [Projection Magecraft (Other)], was limited to works outside Type-Moon.
If it involved weapons from within Type-Moon itself, then it became Shirou Emiya's version of Projection Magecraft instead.
The proof was that Shirou had once tried to project the Holy Sword, Excalibur, and immediately fainted on the spot, then spent three days and three nights bedridden.
Thanks to this divine skill, Shirou already possessed combat power on the level of a Knight of the Round Table at the age of thirteen.
At the same time, his relationship with Morgan also grew visibly closer.
When it came to the succession of the throne, the two of them had already reached an understanding behind Uther and Merlin's backs.
Morgan would become the Queen of Britannia, while Shirou would support her from her side.
They were aligned on the overall direction, but in the details, their thinking differed slightly.
Shirou's plan. After Uther died, he would announce during the coronation ceremony that he was ceding the throne to Morgan, then remain by her side as her subject.
Morgan's plan. After Uther died, she would hold a wedding with Shirou, reign over Britannia as queen, and rule the kingdom together with him.
The servants in the palace often saw the prince and princess walking hand in hand through the courtyard, chatting together. Their relationship looked even closer than that of real siblings.
Of course, Uther and Merlin had been watching all of this as well.
Late one night, seven years after Shirou and Morgan became siblings.
"Morgan-nee-san, I'm coming in."
Shirou had received a letter delivered by a familiar, telling him to come to Morgan's room at midnight.
"My brother, you came."
When Shirou saw Morgan sitting listlessly at the bedside, he quickly walked over, dropped to one knee, and took her hand.
"Did something happen, my Queen?"
Looking worn and exhausted, Morgan said, "I just received some secret information. It has not been announced yet..."
"Morgan-nee-san. You were eavesdropping on Uther and Merlin again!"
Morgan did not deny it. She only lowered her head and murmured, "As part of a political marriage alliance, Father intends to marry me off to King Lot."
"King Lot? You mean King Lot of Orkney?"
Shirou was stunned.
After all, Orkney was the northernmost territory in Britannia, a truly godforsaken place in the middle of nowhere.
Sending Morgan off to marry that far away was, in effect, a way to gradually remove the increasingly famous Morgan from the political center of Britannia.
Those two, Uther and Merlin... have they already started paving the way for my accession to the throne?
"What are we supposed to do, Shirou?"
Morgan grabbed her brother's hand and asked anxiously.
From that day onward, she had made new plans for her life, and placed Shirou in the most important position within them.
If she claimed she had not developed feelings for Shirou that went beyond those of siblings, that would be a lie.
Although Shirou had been the one to confess first, once Morgan learned how sincere he truly was, she could not help being moved.
Now, she was hopelessly in love with Shirou.
Morgan had even dreamed several times that she had married Shirou... and now she was supposed to marry another man? What a joke.
But King Uther's orders were absolute. As his daughter, there was no way she could defy her father's command.
Shirou held his chin and thought for a long time before speaking.
"With the strength we have now, there's no way we can confront Uther head-on, but that doesn't mean there's absolutely no way to turn it down... Let me think."
After that, Shirou proposed several possible plans.
While he was talking, Morgan wore a faintly puzzled expression.
"Um... Shirou?"
"What is it?"
"Why are you able to stay so calm?"
Morgan voiced the confusion in her heart.
When she learned that Father intended to marry her off to someone else, it had felt as though she had fallen into an icy winter lake. She had been so frightened she could not even speak.
But after hearing it, Shirou's reaction was unusually calm. It was not what the girl had imagined at all. She had even thought she might get to see him panic a little.
"I'm your support, Morgan-nee-san. At a time like this, how could I afford not to stay calm?"
"I, I see..."
Shirou continued analyzing the situation.
"Right, what about getting Igraine's support?
You could tell her you don't want to get married somewhere that far away, and that you'd miss your mother too much if you couldn't see her."
Morgan's mind was in complete turmoil. She could not take in a single word of Shirou's analysis.
She realized that what she wanted was not Shirou's support at all.
She did not need something that practical. What she wanted was something gentler, even if it was only a single simple sentence.
"Hey, my brother..."
Carefully testing the waters, she asked, "If I told you I wanted to marry King Lot, what would you do?"
Shirou froze for a moment, then answered seriously, "If that is what would make you happy, Morgan-nee-san, then I would support you unconditionally."
Crash.
The flower vase on the bedside table shattered.
The magical energy erupting from Morgan was like a violent gale, raging wildly through the room.
Shirou was startled.
"Morgan-nee-san?"
The silver-haired princess raised her voice as she demanded,
"My brother... what exactly do you mean by 'my happiness'?"
"I mean..."
Morgan cut him off coldly.
"Shirou! Are you really going to just stand there and watch me marry another man?"
"Uh..."
Shirou looked up in shock and found Morgan glaring at him angrily, her eyes brimming with tears.
The two of them fell silent as they looked at each other.
After a long while, Shirou was finally the one to break the silence.
"To me, Morgan-nee-san, your happiness will always come first...
Since you hate the idea of marrying King Lot, then let's find a way to turn it down."
He thought that would calm Morgan down, but instead it only made her even angrier.
"That's not what I want to hear!!!"
What she did not want to hear was something like, "For Morgan-nee-san's happiness, I'm willing to make any sacrifice."
What she wanted to hear was, "Morgan-nee-san is my woman. I won't let any other man touch her."
Why? Why was it so hard to make him say something like that?
Over the years, Morgan had dropped hints countless times, hoping Shirou would say his feelings out loud again, but every single time, he skillfully dodged the issue.
You obviously like me that much, enough to give up the throne for me... so why are you so unwilling to show it openly?
How hypocritical, my brother...
Shirou's temper began to rise as well. Frustrated, he said,
"I don't understand what you're even angry about."
".........Enough."
Morgan spoke coldly.
"I'm going to accept King Lot's marriage proposal."
...
...
Half a year later, following the marriage arrangement decreed by King Uther, Morgan left the palace and headed for Orkney, at the far edge of Britannia.
In this era, there was no custom of holding a wedding ceremony. Whether noble or commoner, getting married simply meant holding a banquet.
The banquet lasted an entire day. People praised King Lot's wisdom and Princess Morgan's beauty, while offering blessings to the two of them.
Throughout the banquet, Morgan remained expressionless.
She did not spare even a single glance for her new husband, and merely gazed quietly in the direction of the royal palace.
After the banquet came the wedding night.
Morgan hid a dagger in her clothes and walked toward King Lot's bedchamber.
She had already made up her mind.
Although she had been at odds with Shirou for half a year, the only person she loved was Shirou. There was no way she could let another man touch her.
Morgan intended to kill King Lot that very night.
If she did that, she would be able to return to the palace.
King Lot was a lord subject to King Uther, but that did not mean a princess who murdered her husband would go unpunished.
She would most likely be placed under house arrest until Uther died.
That was Morgan's goal. King Uther would never again be able to force her to marry someone else.
Morgan slowly approached the man sleeping on the bed and brought down the dagger in her hand.
At that moment, the man suddenly rolled over and seized her wrist.
"!?"
By the starlight shining into the room, she saw a familiar baby-faced young man.
"Shirou!?"
Morgan cried out in shock.
"Why are you here?"
"To see you, of course, Morgan-nee-san."
Smiling, Shirou took the dagger from her hand and tossed it aside onto the floor.
"No... where's King Lot? What did you do to him?"
After Morgan asked that, Shirou answered with complete seriousness.
"I am King Lot."
"Don't say something so stupid! What is going on here, Shirou!?"
"Do you want the truth?"
"Yes."
Morgan narrowed her eyes and nodded.
Shirou said,
"It took me half a year, but I finally figured out the question you asked me that day.
What would I do if Morgan-nee-san wanted to marry King Lot?
I don't accept it. I hate that."
".........."
Looking at the silver-haired princess as tears ran down her face, Shirou said, word by word,
"Morgan-nee-san is my woman. I won't let any other man touch you."
"Mm...!"
Morgan threw herself into Shirou's arms, and Shirou caught her firmly.
Their hearts finally in sync, the two embraced tightly beneath the moonlight.
...
...
"Um… Morgan-nee-san…?"
Shirou frowned slightly. He could tell something was off with the witch resting against his chest. Her breathing had grown uneven and hurried.
Just as he was about to speak, his body suddenly flipped, and he was shoved down onto the bed.
"Wh-what's going on? Why are you being so rough all of a sudden… that hurts!"
Shirou opened his eyes in confusion, only to find Morgan straddling his waist, her fingers already moving to undo the buttons of her dress.
"Morgan-nee-san! What are you doing?!"
Morgan raised an eyebrow, completely unconcerned.
"Tonight, you are King Lot. My newlywed husband."
Shirou stared at her, stunned.
"That's… not possible, right?"
Morgan rolled her eyes and let out a cold snort.
"Stop talking nonsense. Pleasing her husband is a wife's duty.
Shirou, are you trying to take away my happiness as a woman?
If you understand, then don't struggle. Just lie there and behave."
The black lace dress slipped quietly to the floor.
Seductive yet pure, pale yet full, generous yet slender. The Fairy Queen's body was revealed in its entirety before Shirou's eyes, without the slightest concealment.
Morgan cradled the back of his head, leaning close as she whispered softly into his ear.
"How long are you planning to keep staring? Show me what you've got, like a proper man♡"
…
Notes:
Yamato - is Vergil's trademark dark-forged katana appearing in Devil May Cry
The Aegis - is the iconic weapon wielded by Pyra and Mythra in Xenoblade Chronicles 2