The Way to Return
"Hmm. Is there anything in particular you're curious about? Something you absolutely must know—"
"Return magic. The way to go back to my original world."
"...I thought as much."
The Hero's room was spacious enough for two people to live in comfortably. Hwian slumped into a chair and fixed the princess with a faintly suspicious stare as she stood demurely before the wall.
He had summoned her, but he wondered how useful she would truly be. After going to the trouble of bringing her here, it would be bitterly disappointing if she knew less than he hoped.
Whether she sensed his thoughts or not, Serena let her golden eyes wander slowly around the room. When she spotted the book on the desk, her lips parted in mild surprise.
"Otherworld Summoning Theory... Have you read it?"
"I had time to kill, so I did. It was decent. The sections on return magic were especially interesting."
"The whole volume...? That's impressive. It isn't an easy book."
"I don't need flattery."
Hwian tossed the words out bluntly and picked up the book. Since they both understood the fundamentals, there was no reason to waste time on preliminaries.
"I can grasp that the difficulty is high. It's shitty that you can't send someone back immediately after summoning them, but if that's the reality, there's nothing I can do. Even the sheer volume of mana required makes it obvious."
Any magic that manipulated space devoured mana on a colossal scale. Otherworld summoning, the pinnacle of such arts, demanded a quantity no single caster could ever supply.
It was a grand spell that required constructing an optimized magic circle through endless refinement and burning through mana stones by the truckload before it would even activate.
The recent summoning in Adonia had consumed nearly all the stones the royal family had stockpiled. He still remembered the First Princess from his previous life complaining that the kingdom's finances had been left in ruins.
"There can't be many stones left in the warehouse. Even if you wanted to send me back, you couldn't. That much I understand."
"You know... a great deal about this."
Hwian gave a small nod.
The reason he sat here obediently stemmed from the same logic. If the situation could have been solved by rampaging and issuing threats with all his strength, he would have done it long ago.
Because this was not a problem that yielded to mere desire, he endured the seething frustration and focused on gathering information.
"But the real issue begins here."
He spoke with a sigh. What came next was knowledge no book contained.
"Even if I brought you a mountain of mana stones, you still couldn't send me back. Not because you don't want to, but because you can't. Isn't that right?"
"...!"
"I don't know the reason. Only that quantity alone doesn't solve it. And that the solution is none other than the Demon King."
He deliberately avoided mentioning who had told him. There was no point. Speaking of his pre-regression connections would only arouse suspicion.
"Why?"
He asked. The princess clasped her hands tightly and lowered her head.
Why did the Demon King enter the equation? Why would no one explain anything?
Most had answered his questions with, "I'll tell you once the Demon King resurrects." The king, the nobles, the mages—they had all said the same.
Back then, naive and powerless, he had accepted those words and set out on his journey. Yet by the time the Demon King actually appeared, nearly everyone who had promised answers was already dead.
When he finally stood in a position to receive the truth, no one remained who could give it.
The frustration alone felt enough to drive him mad.
That was why he stared at her. He gazed intently at the Fourth Princess standing motionless before the wall, her fingers fidgeting awkwardly.
Hoping she might offer some answer.
"...The return magic has already been fully researched. The required mana quantity has been calculated as well."
At last she spoke. Her voice was painfully small, laced with torment.
"That's good news. How much, specifically?"
"You cannot simply stack mana stones and cast it like ordinary magic. It requires such extraordinarily pure mana that... only a single stone can be used."
"...What?"
His voice turned to stone.
He had anticipated a purity issue. Since quantity could not compensate, he had expected some technical limitation.
But the number one was beyond anything he had imagined.
Only a single mana stone? He had to power a grand magic without historical precedent using nothing but one stone?
Even the far simpler summoning ritual had required the complete consumption of dozens or hundreds of stones to succeed.
"Stones from mines won't suffice. Those obtained from monsters lack sufficient capacity as well."
She continued in a quiet, steady tone. Her clasped hands tightened instinctively.
"An ultra-high-purity, high-capacity mana stone. ...One from a being on the level of the Demon King is necessary."
Therefore the Demon King had to be subjugated. Even as despair settled back to the starting point, he asked in a voice that still trembled.
"...Is there another way?"
"...."
"Tell me. Is there no other method?"
Defeat the Demon King. Then you can go home.
It was brutally simple.
—And because humanity before the regression had failed to accomplish that simple task, they had been crushed beneath the Demon King and annihilated.
"Ha... ha..."
He rose from the chair. With a trembling hand he swept his hair back and let out a hollow laugh.
The princess knew nothing. She had no idea what kind of life he had lived. How desperately he had struggled. How he had worked until his bones cracked. What thoughts had driven every swing of his sword—she knew none of it.
A frozen continent. A dying world. Rivers overflowing with blood and mountains buried beneath corpses. Within immeasurable loss and pain, what burned inside the mind of a man who had already witnessed the end was raw fury and crushing despair.
With a heavy bang, Hwian's fist slammed into the wall. Breathing hard, clutching his trauma-throbbing head, he leaned his shoulder against it.
Subjugate the Demon King. He had always believed the words the king and nobles repeated were mere threats. He had assumed they were demands made for their own gain. He had never imagined it was the actual process required for his return.
They wanted him to do it all over again?
To lose his comrades, lose his dignity, lose his hope, and return to that day when he lay buried in solitude and despair, waiting to die?
"...I'm sorry."
To him, writhing beneath the flood of memories, Serena spoke. She approached cautiously, gently wrapping her hands around his newly injured fist.
"I'm sorry..."
Her voice trembled—not with fear, but with sorrow and guilt.
The princess knew nothing of the life he had lived. She could not know how much he had suffered before the regression, how deeply he had regretted and agonized.
"I'm sorry..."
Yet still she apologized. Without seeking forgiveness, she simply held his fist and offered her regret.
Her moist voice reached his ears. When he saw her slender shoulders quivering, a question flickered through his mind.
She's crying.
Why did this woman grieve? Hadn't this been the predetermined outcome from the moment they decided to summon a Hero?
The Hero suffers while the royal family grows fat. That was what he had believed summoning meant, and in truth countless royals viewed the Hero as nothing more than a tool for exploitation.
But the woman before him was... different.
After the trouble of summoning a Hero, she made no attempt to exploit the achievement. Instead of taking advantage, she suffered alongside his pain and spoke words of apology.
"...I will help you with every ounce of my strength, Hero. So that you may return."
Self-reproach and devotion—two emotions rarely seen in royalty.
He could not understand why. He had hoped conversation might clarify things, yet he only grew more confused.
Had she not summoned him because she wanted to?
Serena began quietly healing his hand in silence. Looking down at her, he asked.
"Why did you summon me?"
"Pardon...?"
"I asked you in the corridor as well. Wasn't it for the sake of royal authority? ...Yet your answer came close to a denial."
If she had summoned him for authority, she would not have been so helplessly attacked by the nobles earlier. What she sought from his existence was something other than power.
"...."
"...."
Serena's golden eyes met Hwian's dark ones in the space between them.
He saw those golden irises glistening with unshed tears. He saw lips that parted faintly, as though longing to speak.
But after a brief silence, Serena bit her lower lip and offered only a small, self-reproaching smile.
"...It was selfishness. Something muddy and ugly—my own private selfishness."
She confessed it like a sin. Pain clouded her features.
"I should have known from the start that it would hurt you."
Hwian exhaled deeply and walked toward the door.
"...I'm going to clear my head."
With a soft creak and a heavy thud, the door closed behind him.
"I wanted to speak with you."
Alone in the room, Serena whispered.
"...Presumptuously, I wanted to feel your warmth."
The words she murmured never reached him.