Sweet Dreams

Perhaps because of the reward obtained from Sakura, when Sakatsuki performed the imaginary number magecraft, the chant was related to her.

What is an imaginary number? It is an existence that is possible, yet cannot be materialized.

In the HF route of Fate/Stay Night, Sakura was altered by Zouken Matou and, using the Holy Grail could manipulate shadows made of black mud, even materializing them into the "Shadow Giant."

While Sakatsuki did not possess the Black Holy Grail's power, his deeper consciousness—such as negative emotions—was also a source of energy for imaginary number magecraft.

The endless frustration and unresolved desires from Shirou Emiya before his near-death still echoed in Sakatsuki's memories.

A massive, formless shadow formed, like an ink spilt on a canvas, flowing toward the golden light in the dark night.

"It's just a jester's trick!"

The arrogant king ordered, and sixteen Noble Phantasms rang out, piercing the shadow's body like bullets, exploding on the bridge.

When the light dissipated, the shadow followed, reaching toward the place where Gilgamesh stood.

The imaginary number shadow was an unknown entity, much like a mirage risen onto the land. All attacks were ineffective, and the only option was to wait for the shadow to disappear—Gilgamesh in the HF route was engulfed by this seemingly trivial trick.

Although Sakatsuki's imaginary number shadow lacked the Black Holy Grail's overwhelming power, it was still sufficient to handle the Noble Phantasms' attacks.

"What...!"

Gilgamesh's surprised voice faded as he quickly retreated, turning to glare at Sakatsuki. His handsome features were frozen in a cold, murderous gaze.

For the king, losing his composure because of a trivial trick, or retreating from a jester's performance, was unforgivable.

"Do you want to die, magus!"

Faced with the bone-chilling aura that could crush ordinary people, Sakatsuki merely smiled as if the breeze were caressing him. He placed his left hand on his chest, raised his right hand toward the sky in an exaggerated gesture, and elegantly performed a mock bow.

"Then, my performance ends here. I hope the king enjoys a magician's little 'trick.'"

Displacement magecraft activated. A diamond-shaped portal passed through his figure, disappearing along with him.

On the bridge, where flames shot into the sky and quickly dissipated, Gilgamesh's enraged roar echoed.

"Don't let me find you, magus!"

***

The anchor point is confirmed.

Displacement successful.

The diamond-shaped portal unfolded, and Sakatsuki appeared, motionless like a sculpture.

After a long while, a deep breath was heard as Sakatsuki collapsed onto the bed, his chest slightly rising and falling, clearly still shaken.

In the battle against Gilgamesh, it seemed like Sakatsuki had the upper hand—mocking and retreating without harm. But in reality, when the ancient king truly became enraged, Sakatsuki realized the difference between Angelica and Gilgamesh.

One was a lifeless killing machine, a thug for the Ainsworth family—cold and emotionless. The other had once ruled a kingdom, bound the Bull of Heaven, and seized the Elixir of Life.

The difference between them was like heaven and earth.

Sakatsuki had immediately turned to leave, partly because all the imaginary number magecraft had been tested, and there were others to watch out for; partly because Gilgamesh's presence was so overwhelming, that it ignited his fighting spirit.

Once stirred—

Before his most prized treasure was drawn, Gilgamesh would either be dead or severely wounded.

Considering his remaining lifespan and the meticulous plans ahead, Sakatsuki chose to leave, abandoning the imaginary number shadow, and retreating.

Would the shadow cause Gilgamesh harm?

Such things could only be speculated.

It was clear from how Gilgamesh had interfered with Sakatsuki's Imaginary Infiltration that he possessed a weapon that countered imaginary properties. The shadow's attack nearly struck Gilgamesh, but the king had merely underestimated the magic.

"Indeed, compared to Gilgamesh, Iskandar is much easier to deal with."

Sakatsuki sighed, flipping over like a dried fish, placing his arm over his forehead, intending to rest for a while.

With the imaginary number magic experiment complete, and the Masters of the Holy Grail War still not gathered, he decided to enjoy the last peaceful moments with Miyu and Sakura before the war truly began.

Knock! Knock! Knock!

A soft knock on the door, followed by a cautious voice from outside.

"Oni-chan, are you asleep?"

In a swift motion, Sakatsuki sprang up from the bed, took a deep breath... and opened the door, putting on a calm facade.

Moonlight poured through the glass window, casting light on the hallway, where Miyu, dressed in her bear pyjamas, looked a bit shy, her face flushed.

She didn't say anything, but Sakatsuki understood.

"I remember you prefer the tatami room, Miyu. Are you not used to this room and couldn't sleep?"

The tatami room was a traditional Japanese room, where walking barefoot on the rush mats felt like wandering in nature itself. In the Fate/kaleid liner worldline, both the Sakatsuki and Emiya families lived in traditional Japanese-style houses, and for Miyu, this was likely her first experience with such a grand and bright Japanese-style room.

"Y-Yes, it's just... the room feels too big."

She mumbled, seeming a bit embarrassed to admit she was still scared to sleep alone. She nervously fidgeted and softly spoke.

"It's a bit scary when the lights are turned off."

Sakatsuki couldn't help but laugh softly. Before she could run away in embarrassment, he stretched out his arms and scooped her up, laughing as he placed her beside him on the bed.

"Then tonight, sleep with me. I'll keep you safe."

"Mhm..."

Miyu's face pressed against his chest, and after a while, she quietly responded in a barely audible voice.

The familiar, reassuring scent enveloped her once more.

There were still many things she wanted to say and many questions to ask, but in the end, Miyu closed her eyes and drifted into a comfortable dream.

Beside her, the once-red-haired, now white-headed young man rested against the bed's headboard, his golden eyes lowered as he looked at her with gentle affection.

As for the fact that Servants could become spirits... he had already ignored that detail.

As Shirou, as Sakatsuki, as her older brother...

Sweet dreams.