I, Rin Tohsaka, Will Be a Demon God in Type-Moon

"Sorry, Rin. Dad can't understand your magecraft research. It seems you've completely surpassed me in some areas. Rin, since you've encountered a problem you can't solve, why don't you go up and rest for a while? Clear your head before continuing your research."

Rin nodded helplessly, tidied up the crystal shards on the table, and left the basement.

Rin went upstairs along the stairs. Seeing Sakura waiting for her at the basement entrance, her mood immediately improved, and she happily started chatting with Sakura.

Aoi Tohsaka, who was tidying up the house, smiled happily as she watched her two harmonious daughters.

Basement.

Tokiomi Tohsaka carefully put away the papers Rin had written the Runic Alphabet on, then shook his head.

"Rin, it's fine, but her personality is too rash. Sigh! She crumpled something so important into a ball and just threw it on the ground."

He then went to the table, took out a small box from his pocket, and opened it to reveal an ancient snakeskin. It was the holy relic Risei Kirei had found for him at the church today.

Tokiomi Tohsaka studied the snakeskin for a long time before slowly closing the box and putting it back in his pocket. He then took the crystal powder from the side and skillfully drew a magic circle on the table.

"Risei, thank you so much. According to our previous plan, I hope Kirei can visit tomorrow as a disciple."

Then, Risei Kirei's voice came from the magic circle.

"Yes, Tokiomi. I will arrange for Kirei to visit the Tohsaka Estate tomorrow."

"That's wonderful. With your and Kirei's help in this Holy Grail War, we are bound to win..."

That night, Rin was sleeping in her bed when she suddenly heard a system prompt. She put on her coat and stood by the window, looking at the quiet courtyard, and slowly opened the system panel.

As Rin's research into Stiyl's magecraft deepened, another column was unlocked on the system. Rin clicked on 'Exchange,' and a dazzling array of magecraft from the A Certain Magical Index world was displayed before her.

Rin kept scrolling through the exchange column, looking at the grayed-out, unexchangeable magecraft. The faster she scrolled, the faster she reached the bottom.

"System, why can't I exchange for these magecrafts? And what's the difference between exchange and reward?"

"The power of magic is the power of miracles. Only when the host achieves miracles that are impossible for humans can they qualify for exchange. Rewards will only be given to the host after they achieve deeds that are widely spread among humans."

Rin thought about the Holy Grail War that would begin in a little over a year. After a moment of thought, she made a decision. She would fight her father tomorrow to demonstrate the power she had promised to achieve and to test if she could get a reward. A 5-year-old girl defeating an adult Magus should meet the conditions, right?

Section 3 Chapter 3: Rin Tohsaka's Path to Demon God, Roar, King of Witch Hunters!

The next day.

As the school bell rang, Rin agilely stuffed the pre-school enlightenment books on her desk into her schoolbag. After packing the books, Rin carried her schoolbag and ran quickly to Sakura's classroom door.

Soon, Rin arrived at Sakura's classroom door and immediately saw her sister waiting for her with her schoolbag. Rin immediately waved happily at Sakura.

Sakura politely greeted her classmates before slowly coming to Rin's side.

"Sister."

"Mm, Sakura, let's go quickly."

Rin grabbed Sakura's hand and led her away from the campus (kindergarten) quickly.

Walking through the campus, the two sisters soon arrived at the school gate. They looked around strangely. Normally, Aoi Tohsaka would have been waiting for them at the school gate after school to pick them up, but today she was late.

Seeing Rin impatiently looking into the distance, hoping to see Aoi Tohsaka, Sakura asked.

"Sister, why are you in such a hurry to go home today?"

Rin pulled Sakura closer and whispered in her ear.

"Sakura, today I plan to go home and challenge Dad. I feel like I can fulfill our promise now."

Sakura looked at Rin in surprise.

"What? Sister, you're going to challenge Dad?"

"Keep your voice down, Sakura. That's right, I'm going to challenge Dad, so you'll never have to worry about being sent to that old bug's house again."

"But Sister, Dad is so strong. You've only been studying magecraft for less than a year. Can you beat him? And what if one of you gets hurt? Oh, and why do you call Old Man Matou 'old bug'?"

Rin had intended to make Sakura happy, but she didn't expect Sakura to first think about whether she could avoid being sent to another family, but rather about whether she and Tokiomi might get hurt. She had to force an explanation.

"Don't worry, Sakura. Dad will definitely not let me get hurt. And like you said, Dad is so strong, how could he get hurt? Zouken Matou, doesn't that guy seem like a cockroach? What's wrong with calling him an old bug?"

Sakura then nodded in relief.

"Yes, how could Dad hurt Sister? And Dad is so strong, how could he get hurt?"

Rin thought to herself that it would be great if Tokiomi Tohsaka were truly that strong. In her memories from her past life, Tokiomi Tohsaka was easily backstabbed, earning him the title of "Pot of this World," which meant he wasn't strong enough.

Soon, Aoi Tohsaka appeared at the school gate driving a car. Sakura nudged the pondering Rin, indicating that their mother had arrived.

Rin gave up thinking and pulled Sakura to the car. She opened the rear door, let Sakura get in first, and then got in herself and closed the door.

"Mom, why are you so late today?" Rin asked curiously.

"Sister, Mom is only five minutes late."

"Sakura, don't tease me."

Aoi Tohsaka looked at her daughters bickering in the rearview mirror and replied happily.

"I'm sorry, Rin, Sakura. We had a guest at home today, and I was busy tidying up the guest room, which delayed me a bit. Can you forgive me?"

Sakura, who was pinned under Rin, quickly stopped bickering.

"Mom, it's okay. Sakura doesn't blame you, and Sister doesn't blame you either, right?"

"Sakura is so sensible. Rin, are you blaming Mommy?"

Rin released Sakura from under her, sat up, and asked curiously.

"Of course not. By the way, Mom, who is the guest today? And they're staying at our house?"

"Ah, the guest is your father's new disciple, named Kirei Kotomine. He's a very polite person. Rin, Sakura, you should learn from him. Especially you, Rin, you must be polite, understand!"

Hearing the name Kirei Kotomine, Rin's pupils contracted. That's right, this guy was the murderer who would kill her father later, and he would also play her for a fool for the next 10 years.

Aoi Tohsaka, looking at the suddenly dazed Rin through the rearview mirror, slowed down, turned her head to look at Rin, and asked nervously.

"Rin, what's wrong?"

"Ah, it's nothing, Mom. I just remembered something."

Aoi Tohsaka breathed a sigh of relief when she saw that Rin was fine.

"If nothing's wrong, don't be so jumpy..."

Soon, the car returned to the Tohsaka Estate. As soon as the car stopped, Rin opened the car door, grabbed her schoolbag, and dashed into the house.

After entering the house, Rin quickly found Tokiomi Tohsaka and Kirei Kotomine, who were drinking tea in the living room, by following the sound.

Kirei Kotomine, seeing Rin walk into the living room, curiously sized up the genius daughter his teacher had spoken of.

"Rin, you're rushing around. Have you forgotten the Tohsaka family's motto? And this is Kirei Kotomine, my new disciple, and your senior brother. Come and greet your senior brother."

Rin quickly tidied her appearance before slowly speaking.

"Senior brother, hello. My name is Rin Tohsaka. Please guide me in the future."

Tokiomi looked at Rin and nodded with satisfaction, then spoke.

"Rin, what is it?"

"Father, I want to challenge you. I want to fulfill our promise."

Tokiomi Tohsaka looked at Rin with some surprise. 'Does this child have the confidence to fight me now?' But then he thought that his daughter was only 5 years old, and no matter how much of a genius she was, she couldn't possibly fight him. To avoid crushing Rin's confidence, after some thought, Tokiomi Tohsaka slowly stood up.

"Rin, how about this? Kirei is here too. This time, you will fight Kirei. If you can defeat Kirei, then I will recognize that you have fulfilled the promise. Kirei, I'll trouble you with this."

Kirei was slightly stunned, then nodded in agreement.

Rin tilted her head and glanced at Kirei Kotomine. 'Should I teach this future arch-enemy a lesson now?'

Seeing Rin's expression, Tokiomi reminded her.

"Rin, don't underestimate Kirei. Before he became my disciple, he was a representative of the church. If you underestimate him, you'll suffer. Alright, come with me to the back mountain."

Seeing Tokiomi Tohsaka get up and leave the living room, Rin and Kirei Kotomine immediately followed Tokiomi Tohsaka towards the back mountain.

Aoi Tohsaka and Sakura, who had just entered the house, saw the three people preparing to go out and asked curiously.

"Darling, dinner is almost ready. Where are you taking Rin and Kirei?"

Tokiomi Tohsaka smiled at his wife and second daughter.

"Rin's magecraft has been improving very quickly recently, and she herself has made a request. I'm taking her to do some pre-dinner exercise. Aoi, you and Sakura arrange dinner. We'll be back soon."

Aoi Tohsaka looked at the confident and elegant Tokiomi Tohsaka and nodded reassuringly, then led Sakura into the house.

The back mountain behind the Tohsaka Estate.

After setting up a barrier to keep people away, Tokiomi Tohsaka came to Rin and Kirei Kotomine's side.

"Kirei, although I've always boasted that my eldest daughter is a genius, she's still a 5-year-old child after all. Please go easy on Rin. Rin, you also be careful, understand?"

Kirei Kotomine nodded.

"Master, I understand. Junior sister, you go first."

Hearing Tokiomi Tohsaka and Kirei Kotomine's conversation, Rin pouted, feeling displeased that Tokiomi Tohsaka looked down on her. She thought to herself, 'Just you wait, I'll surprise you all soon. I have to teach this future enemy a good lesson too.'

"Hmph, don't underestimate me. Watch me take you down in one go, 'Senior Brother'."

Then, she threw a handful of crystal shards inscribed with Runic Alphabet into the surroundings and raised her right hand to begin chanting.

"MTWOTFFTO (One of the five great elements that construct the world)

IIGOIIF (Oh, great flame of the progenitor)

IIBOL (That is the light of grace that nurtures life)

AIIAOE (That is the light of judgment that punishes evil)

IIMH (While bringing peace and happiness)

AIIBOD (It is also the misfortune of cold darkness and freezing)

IIZF (Its name is Flame)

IIMS (Its duty is Sword)

ICR (Manifest!)

MMBOP (Devour my body and turn it into power)

─── Innocentius (King of Witch Hunters)!"

"ROAR!"

The giant made of flames roared for the first time in this world.

Section 4: Rin Tohsaka

Host: Rin Tohsaka

Age: 7

Attributes: Five Great Elements

Strength: E-

Endurance: E/A+ (A+ when supplied with sufficient magical energy and Water of Life)

Agility: E

Magical Energy: C+

Luck: ??

Noble Phantasm: None

Magecraft Rank: C+

Magecraft Field: (Possesses a systematic set of Magecraft)

Runic Alphabet: The Runic Alphabet consists of twenty-four magical symbols representing "mystery" and "secrets." It is a magical language used by Germanic peoples starting from the second century AD, and it is also the origin of Old English.