Nezuko is initially 12 years old in the manga. As the story unfolds, her age doesn't change significantly in a traditional sense, but her character development is quite remarkable.
I don't know if it'll meet your needs, but I'll try my best to recommend a novel that's most relevant to your description. Journey to the West: From the moment I caught Sun Wukong. This book is a fantasy sword and magic novel written by the author, Cola. The general plot of this novel is as follows:
The male protagonist transmigrated to the Heavenly Court and became a small soldier. In a crusade, he unexpectedly obtained powerful strength and defeated Sun Wukong, becoming famous in one battle...
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Journey to the West: Killing Tang Sanzang with a Single Stick at the Beginning was a Xianxia-Mythological Cultivation novel written by the author Wu Yu2. The general plot of this novel was:
After traveling through the world of Journey to the West, he became Sun Wukong, who was being reprimanded by Tang Sanzang.
A rude monkey? Indiscriminately killing the innocent?
I can tolerate this, but what I can't tolerate the most is that you actually chanted the Golden Hoop Incantation?
Good, good, good. You guys can go on your own. I won't play with you anymore!
As soon as he finished speaking, Sun Wukong took out the Golden-Hooped Rod and immediately killed Tang Sanzang!
"Hehe, no one has ever scolded me since I was born. Who do you think you are, hetui!"
[Ding! Enjoy the Journey to the West selection system activated. Host, please receive the reward for killing Tang Sanzang…]
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"The Great Demon Sun Wukong" was a Xianxia-Cultivation Civilization novel written by the author, Tang Sanzang. The general plot of this novel was:
Journey to the West only told the story of the journey to the west.
But was it really that simple?
Now, let me tell you, the Journey to the West is just the beginning. The story is not over.
Tang Sanzang, Sun Wukong, Zhu Wuneng, Sha Wujing, and Little White Dragon. The path of these five people would continue.
When I knelt in front of the Buddha and took off the golden hoop, I finally remembered who I was.
Who am I?
I'm the Great Sage, Heaven's Equal, Sun Wukong.
I am the great demon Sun Wukong.
I am the invincible Sun Wukong.
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"The Ninth Life of the Tang Monk" was a Xianxia-Mythology-Cultivation novel written by the author, King Toad. The general plot of this novel was:
He punched Tang Sanzang and blew up Journey to the West.
Going against the heavens, stepping through the firmament…
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Journey to the West: Don't mess with Monkey Sun, he's crazy. This book was written by a strong fisherman. It was a Xianxia-mythical cultivation novel. The general plot of this novel was:
He had transmigrated into the world of Journey to the West and became Sun Wukong. Sun Wu realized that as long as he worked hard to cultivate, he would be punished and even lose his lifespan. However, when he was decadent…[Your negative behavior received punishment: Constitution +10, Bloodline +10, Lifespan +10] and when he was injured! [You have been baptized by lightning: Innate Tai Qing Divine Lightning Bloodline +99, Constitution +500][You have been burned by the Grand Sun Primordial Fire: Grand Sun Primordial Fire +100, Constitution +1000] Could this be considered as the reverse direction of cultivation? Therefore, Sun Wukong completely let go! Whoever dares to bully me, I will fight to the death. You either kill me today or I'll kill you tomorrow! Subhuti: I was so angry that the monkey ran away after setting Mount Fangcun on fire. Dragon King of the East Sea: I already gave you the Jingu Staff. Why did you take my daughter away? Jade Emperor: Wasn't it just a formality? That monkey had already sunk the Heavenly Court! Tathagata: Don't get the scriptures, don't get the scriptures, why provoke this monkey? Was he crazy?
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"The Fist of the West: Tang Sanzang" was a fantasy novel written by the author, Bai Ju. The general plot of this novel was:
"Wukong, are you willing to follow me to the western paradise to obtain scriptures, or am I sending you to the western paradise?" Holding Sun Wukong's neck, Tang Chen felt helpless. He smashed the Five Fingers Mountain with a punch and provoked Tathagata. This was not what he should do as Tang Sanzang. Since he could not reason with him, he would beat him to a pulp. If there was anything in the world that could not be solved with one punch, then he would punch him again! Of course, before that, I still have to hide for a while…
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Journey to the West: Pilgrimage? Sorry, I'm Here to Steal the Classics."This book was written by the author, Yang Xixi. It was a Xianxia, mythological, and cultivation novel. The general plot of this novel was:
At the foot of the Five Elements Mountain.
"Bald monk, you're finally here. Hurry up and save me, I'll help you get the scriptures."
Tang Sanzang opened the Bodhisattva's Guide to the West and glanced at the monkey that was pressed down the mountain. He hesitated for a moment and muttered to himself,
"Is this the monkey that I wanted to watch when I turned on the TV back then?"
"Back then, because of this monkey, he didn't even look at the Seven Celestial Maidens, nor did the King of the Kingdom of Women…"
"I really want to pinch it."
Sun Wukong was speechless.
"What?" Sun Wukong, who was pressed down at the foot of the mountain, was stunned for a moment."Bald monk, what do you mean by saying what's on your mind?"
Sun Wukong: "Forget it, forget it. I'm the Great Sage Equal to Heaven who wreaked havoc in the Heavenly Palace 500 years ago. It's because I committed…"
Tang San Zang lightly raised his palm and smashed the Five Elements Mountain."Alright, cut the crap. Are you going to the Western Paradise with me?" Or should I send you to the afterlife?"
Sun Wukong was speechless.
On the road to learning the scriptures!
Zhu Bajie: "Eldest Senior Brother, bad news! The monster has been captured by Master again!"
"Second Senior Brother," said Friar Sand,"Master is teaching the demon with a stick again."
Arriving at the Western Paradise!
Tang San Zang said,"Mighty Heavenly Dragon, how dare you hide the true scripture!"
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"A Man's Journey to the West, Rebellion and Become Strong" was a fantasy novel written by the author, Xiang Chenxiang. The general plot of this novel was:
Sha Shaojun transmigrated to the West and became Sha Wujing. He obtained the Rebellion and Strengthening System and started all kinds of fancy rebellions. Rebellion meant becoming stronger and starting a life of magnificent counterattack! After obtaining the scriptures, he returned to asceticism and was targeted by the three worlds, six paths, and various factions, as well as the western paradise and the celestial heavens. Tang Xuanzang, Sun Wukong, Zhu Bajie, and Little White Dragon stood up for him. The 33 heavens fought against Primordial Heaven Supreme. The three races took the opportunity to cause trouble. He turned the tide and calmed the three worlds. After thousands of years, Young Master Sha had finally become a Heavenly Emperor!
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"Crossing Wukong and Fighting Westward Journey" was a Xianxia-Mythological Cultivation novel written by the author, Amorous Sword. The general plot of this novel was:
In the year 3000 AD, the young Sun Xiaokong was transported to the world of Journey to the West by the Milky Way Peace Control Center because of a Journey to the West. With a mysterious mission, from God's perspective! Journey to the West Again!
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Sun Wukong's Life Simulator was a Xianxia-Mythological Cultivation novel written by the author Yue Buxue. The general plot of this novel was:
Flowerfruit Mountain became the king, and Fangcun Mountain sought immortality. From the Eastern Sea to the Netherworld, then to the Heavenly Palace, they caused a huge commotion. After being suppressed by the Five Elements Mountain, he went to the Western Heaven to obtain scriptures. He led a horse and fell down. After 81 difficulties, he finally became the Fighting Buddha. Looking at Sun Wukong's life, was he considered a success or a failure? Or was this a complete tragedy? And all of this was the result of a scheme? Or was it because of his personality? What kind of future would Sun Wukong create when he had the life simulator?
A simple Nezuko and Zenitsu fanfiction could be that they go on a journey together. Along the way, they encounter other demon slayers who are initially skeptical of Nezuko. But Zenitsu stands up for her, explaining that she's different. This shows the depth of their friendship and how Zenitsu has come to trust Nezuko completely.