At the sight of the warm sunlight spilling through the cave entrance, the demon reacted as though he had seen the most terrifying thing in the world. He backed away almost instinctively, retreating deeper into the cave. Only after making certain that not a single ray of that warm sunlight could touch him did he breathe a small sigh of relief.
Only then did the demon notice that Su Mu had not stopped walking. He was still heading toward the cave entrance and was almost within reach of the warm sunlight pouring in.
"You'll die if the sunlight touches you."
The words came from the demon's mouth in a trembling voice steeped in terror.
Su Mu paused briefly. He could feel his body's instinctive fear, an inexplicable dread gripping his heart, as though he were staring death in the face.
Sunlight, something utterly ordinary to humans, now seemed to Su Mu like the most terrifying thing in the world.
Just like a demon's instinctive craving for human flesh and blood, the fear of sunlight was etched deep into its instincts. In fact, as he drew closer to the sunlight, even his body's craving for flesh and blood vanished. All that remained was fear of the sunlight before him, his instincts urging him over and over to stay away from its warmth.
Su Mu stood still, gazing at the sunlight spilling through the cave entrance. What had once been utterly commonplace to him as a human was now something he could only long for, forever beyond his reach as a demon.
He could feel the boundless terror filling his heart, yet a relieved smile appeared on his face.
For at that moment, he could no longer feel even a trace of the craving for flesh and blood that had plagued him every waking instant.
He could sense that his body's instinctive craving had not disappeared. It had merely been suppressed by his instinctive fear of sunlight-the terror of facing death itself.
To Su Mu, death was frightening too, but at least he had gained a brief chance to breathe. His will, constantly strained by the struggle against his body's craving for flesh and blood, could finally find a little respite. Like a string stretched so taut it was about to snap, it had finally been allowed to slacken.
He felt his body's instinctive fear of sunlight. He felt every cell trembling in terror of it, his body constantly signaling him to retreat into the darkness deep within the cave. Even so, he slowly approached the place where the sunlight fell, inch by inch.
Though his instincts resisted him relentlessly, he still reached out, slowly but firmly, extending his hand toward the sunlight.
"Madman, madman..."
Watching Su Mu's actions from behind, the demon nearly shrieked. He looked at Su Mu as though he were a monster.
As his fingers drew steadily closer to the warm sunlight, the fear of death almost completely consumed his heart. Still, trembling, he slowly extended his fingers into the light.
When the sunlight fell upon his fingers, he could see them slowly dissolving like snowflakes beneath a blazing sun, disappearing from the world little by little.
Su Mu stood where he was, quietly watching his fingers disappear bit by bit. Only then did he withdraw his hand and retreat into the darkness deep within the cave.
Only after he had moved far away from the sunlit area, his entire body enveloped in darkness, did its instinctive trembling begin to subside.
"You're completely insane. Aren't you afraid of dying?"
The demon beside him stared at Su Mu as though he were a monster. Standing in sunlight was something no demon dared even imagine. Even the progenitor of demons, Muzan Kibutsuji, did not dare expose himself to the sun.
Su Mu ignored the demon beside him and lowered his gaze to the fingers the sunlight had melted away, studying the wounds left behind. Normally, injuries like these would have healed almost immediately, new fingers growing in their place. Now, though he could feel the wounds healing, the process was dozens of times slower than usual, if not more.
"It seems sunlight doesn't just destroy a demon's body. It also drastically slows the recovery of any part it injures."
Su Mu stared at his fingers and murmured under his breath.
"You really are insane. You put your fingers in sunlight just to find that out? Completely insane. Even getting slashed by the Demon Slayer Corps' Nichirin Blades is better than facing sunlight directly."
The demon beside him stared at Su Mu as though he were a monster. He had seen plenty of demons, but never one as mad as this man.
Demons could not stand in sunlight. That was common knowledge among them, something they knew by instinct. No demon dared test it. Even someone as powerful as Muzan Kibutsuji did not dare stand beneath the sun.
There was no demon in this world capable of standing in sunlight.
"We're creatures of darkness. No demon can stand in sunlight."
The demon spoke softly beside him.
"No demon can stand in sunlight?"
Su Mu could not help murmuring.
"That's right. Don't entertain any fantasies about it. That's one of our flaws as demons."
The demon beside him continued, a trace of resentment in his voice. After all, he had once been human. Basking in sunlight, something utterly ordinary for a human, had become forever beyond his reach after he became a demon.
Su Mu simply stared at his fingers in silence. The demons of this world were like sewer rats, forever forced to hide in darkness. Even the progenitor of demons, Muzan Kibutsuji, could not overcome this flaw.
But if he remembered correctly, Nezuko, who eventually became a demon, had overcome this flaw and become the first demon capable of standing in sunlight.
And the reason Nezuko had been able to overcome that flaw was that she had eaten the flowers of the Blue Spider Lily.
"Blue Spider Lily."
Blue Spider Lily, Su Mu murmured inwardly. Muzan Kibutsuji had sought it for hundreds upon hundreds of years without success, but Su Mu felt he had to get his hands on it. Whether it was a demon's uncontrollable craving for flesh and blood or being forced to hide in darkness like a sewer rat, neither was something he could accept.
As he recalled, the reason Muzan Kibutsuji had failed to find the Blue Spider Lily for all those centuries was that it only bloomed during the day.
How could demons, unable to stand in sunlight and forced to hide in darkness, ever find a Blue Spider Lily that bloomed only during the day?
For him, however, knowing this meant that finding the Blue Spider Lily was not impossible.
If he remembered correctly, Blue Spider Lilies grew near Tanjiro Kamado's home.