Transparent World × Eyes of Truth

A cup of hot tea dispelled the chill.

Tanjuro put down his teacup and began the ritual to appease the Fire God.

Let the children do whatever they want; the matter of putting on the formal attire is something that needs to be handled by Roy, the older brother... Tanjuro had already taken out the ritual attire and placed it on a cushion to the side. The reason he wasn't wearing it was that he had been waiting for someone, and thankfully, he had.

Wide robe sleeves... a rope twisted into a braid... a fire-patterned mask covering their faces, Tanjuro helped Roy to his feet, descended the steps, and stood in the courtyard.

Roy leaned against a pillar, watching quietly...

The man took a deep breath, began a "Waltz," and moved gracefully...

Just then, Mother Kie came over with a plate of tempura. The freshly fried shrimp emitted an enticing aroma. The children, tired from playing, swarmed around her, but Kie slapped each of them away, saying, "Let your eldest brother eat first!"

No one dared to provoke their mother, so Takeo and Mao reluctantly withdrew their hands and stared longingly at Roy.

Roy smiled, symbolically pinched one and put it in his mouth, then continued watching Tanjuro dance, surrounded by the clamor of "Slow down, don't grab it!" and "Leave some for your big brother!"

Once, twice, Tanjuro danced with abandon, like a leaping fire sprite, his sleeves billowing out a flurry of snowflakes... Gradually, Roy narrowed his eyes, realizing something was wrong.

Why is it that my father dances with more rhythm than I do?

"Nii-san, do you want more?" Tanjiro, chewing on half a shrimp, struggled to snatch two more from Takeo and Shigeru's hands and handed them over... Roy, however, was completely oblivious, staring blankly at Tanjuro, his eyes filled with "Nen," his mind racing, a word flashing through his mind—

Transparent World!

The highest state of being is to live with complete clarity.

Undisturbed by worldly affairs, one can immerse oneself in the self, truly achieving a state of egolessness, otherlessness, and thoughtlessness. Only then can one amplify perception, keenly grasp everything around them, and make the most rational reactions and judgments, such as... slowing down the opponent's movements, capturing their attack route, and seeing through their weaknesses.

Summarize-

"There's nothing new under the sun..." Roy murmured softly.

Tanjiro: "Nii-san... what are you saying..."

I said there's nothing new under the sun...

[Hint: [Send]: "Eyes of Truth" has been loaded (Note: Based on [Train]'s "Sun" imagination, the host can see through illusions and anticipate the enemy's moves, for a time of 0.1 seconds)]

"Pfft~" Two bright flames ignited in Roy's pupils. Tanjiro paused in the hand that was handing over the Nii-san, met his brother's gaze, and felt a chill in his heart, as if his whole body had been seen through. Startled, he subconsciously withdrew his hand, but Roy had already caught his movement, grabbed it, pinched a tempura and threw it into his mouth.

Tanjiro paused for a second, rubbed his eyes, and thought, "What? It felt like my Nii-san's eyes were just glowing?"

"Chew... chew..." After swallowing a piece of tempura, Roy's gaze swept around before settling back on Tanjuro. Without turning his head, he said, "Nezuko, don't let Delia suck her fingers."

In a corner of the corridor, Nezuko, who was nestled by the fireplace and coaxing Delia, glanced at her suspiciously... Her little sister was clearly playing with the Bamboo-Copter Nezuko Nii-san had just bought, how could she have time to suck her thumb? But then... With another glance, Delia's little hand slid off the dragonfly's tail and skillfully put it in her mouth.

Nezuko: "..

He turned to look at Roy.

Eiichiro sat quietly with his back to her, the "sun" in his eyes "poof~" going out, lasting only 0.1 seconds.

Then, Roy felt the world fade in lines before his eyes, and in the blink of an eye it returned to normal.

[Development]...[Practice] The natural results of following the trend, such as "stretching" and "illusion" for Hisoka... "control" and "possession" for Illumi... "theft" and "collection" for Chrollo... "Mind Monkey" and "Buddhist principles" for Netero...

What am I?

I am the "Sun," capable of patrolling on behalf of Heaven, Dispelling Darkness, and radiating boundless light to save Human Realm... Tsugikuni Yoriichi, you must have thought the same thing back then.

"Hinokami Kagura - Flame Dance..."

In the wind and snow, Tanjuro finished his last dance move and stopped barefoot.

A corner of the fire-patterned mask was lifted by the wind, and Roy stared at it in a daze in the long corridor, vaguely seeing what appeared to be a person.

He had deep red hair, and flame- Demon Slayer Mark were branded on his forehead. Looking across the divide between life and death, his figure overlapped with that of his father. He smiled gently at him and said, "Eiichiro, help me take off my clothes."

"Yes."

Roy snapped out of his daze, and his father sat down next to him, revealing a knotted rope behind his back.

He stepped forward and untied the knot, simultaneously clearing away the fog in his heart and glimpsing more sunlight.

"This is a perfect New Year's Eve." He thought to himself. That night, he had New Year's Eve dinner with his family and chatted for a long time. He then carried Takeo and Shigeru, one in each hand, and led Tanjiro back to the heated kang bed in the west room, where he lay down fully clothed.

Unlike towns, you can still faintly hear the sound of firecrackers in the mountains...

In the midst of tranquility...

After a day of merriment, Takeo and Shigeru fell into a deep sleep... Tanjiro was left lying next to Roy, his eyes opening and closing repeatedly, seemingly still immersed in the joy of the festival, too excited to sleep.

"Hey~ Nii-san, are you asleep?" Tanjiro turned over and looked at Roy. He hadn't seen his older brother for several months, and he had grown so much... no, he had grown so much taller... He was a head taller than him... He was only half a head taller than him before he left home. The Sun-Earring Boy secretly compared himself to him and pouted in frustration.

Roy, with his eyes closed, said, "Asleep."

Tanjiro:

Regardless, he continued, "When is Nii-san leaving?"

"Tomorrow."

"Hmm... Ah? Tomorrow?"

"Yes."

Why so early?

Even the blankets can't warm up properly...

"Because time is of the essence." Roy calculated the time; there were still two years until the birth of the youngest child in the family, "Rokuta."

It was at that moment that Muzan appeared and killed the Kamado Family.

Roy had no habit of procrastination. From the very first day he became the eldest son of the family, he decided to nip the scumbag boss in the bud and let him experience what it meant to be "Merciless Sun"!

Tanjiro fell silent. He opened his mouth, wanting to ask again... Was it because of the Demon?

Seeing that Nii-san seemed unwilling to say anything more, he simply gave up, pulled the blanket over his head, and covered his head.

As night deepened, our breaths, a harmonious blend of yours and mine, echoed in the snowy night.

The silly little brother fell asleep almost immediately. Without his disturbance, Roy got out of bed, threw on his clothes, and pushed open the door...

In the long corridor outside the door, the man nestled against the fireplace, warming a pot of tea...

Quietly watching her eldest son, who was growing taller and taller each day, she uttered a startling statement. "Eiichiro, congratulations on awakening the [Transparent World]."