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"Eh? You want me to be a master of Chaldea?" Shirou asked.

"Yes…for a while. You see, when we did a health check on you when you arrived here, we found out that you're compatible with the summoning system here in Chaldea." Da Vinci replied.

"I see. But why though?"

"Well…we're a bit short on manpower here…and Fujimaru-kun is the only master here actually."

Shirou's eyes widened upon hearing Da Vinci's words. "Really?" he asked to which Da Vinci nodded in reply. "So…you're telling me that Ritsuka is technically the master of every servant here?"

"Yes. Originally, there were supposed to be 40 masters, but-"

"40 masters?! Are you serious?!" Shirou interrupted, to which Da Vinci nodded in reply. "Jeez, 40 masters…just what kind of organization Chaldea is…?" he thought to himself. "Okay, I can see why you're asking for help, but one question. Why are you asking me? Was this your idea?"

"Well, a part of it is due to the mentioned compatibility earlier. The other reason was that…Arturia and her friends came up with this idea."

Shirou was surprised. "They did?"

"Yeah…"

(Earlier…)

Da Vinci let out a sigh as she took a sip of coffee. "Jeez, to think our mystery resident happens to be a former master…and everyone in the cafeteria happened to know him at the same time…" she thought before looking at a paper beside her on her desk. "Speaking of which, I can't believe that despite coming from an alternate universe, he has great compatibility with Chaldea's summoning system…maybe he could be a new master for Chaldea…"

It was then a few knocks were heard from the door. "Hm? Who could it be?" she thought to herself as she got off her chair and went towards the door. As the door opened, it revealed a guest she was not expecting to see.

Or rather, a bunch of certain guests.

For a moment, the genius inventor was speechless at the situation in front of her. "Um…can I help all of you?"

Immediately, they all said one thing.

"Please get Shirou/Emiya-kun/Senapi/Onii-chan/Shero to stay here as a master!"

"Eh?"

(Back to the present…)

"And that's how it happened." Da Vinci said as she was done recalling the story.

Shirou was completely stunned after hearing Da Vinci's story. "So let me get this straight, Saber and the others wanted me to stay here by asking you to make me a master here?" he asked.

"Yes. Well, what do you think?"

For a moment, Shirou was thinking about the offer. "Hm…this offer doesn't seem that bad to me. Plus, Saber is here…although I'll make sure if Chaldea is truly an organization dedicated to the protection of humanity. Not to mention that the King of Heroes is here and is probably thinking of killing me…well, I'll deal with that when that time comes…"

"Shirou? Is there something wrong?"

"No. Just thinking about the offer…and I'll accept it."

Da Vinci's face lit up in excitement. "Really?!" she asked to which Shirou nodded in reply. "Great! I'll set up the paperwork for you then!" She then went towards a corner of her desk before bringing back a stack of papers. "Okay, all you need to do is to sign them."

At that moment, Shirou was a little shocked. "Wait. I really need to sign all of these papers to become a master?" he asked in disbelief.

"Yes. Why?"

"Well…since when did becoming a master involve paperwork?! Usually there's supposed to be a magic circle of some sort, not paperwork! This is more like a job interview at a company in this situation!"

Da Vinci let out a chuckle. "Things have changed."

(A few days later…)

"Well…?"

Da Vinci let out a smile. "Great news! Your application to Chaldea has been accepted! As of now, you are a master of Chaldea! The entirety of Chaldea's staff has accepted you! Anyways, welcome to Chaldea, Emiya Shirou!" she said as she raised her hand for a handshake.

"Yeah." Shirou replied as he shook her hand.

Soon, Shirou left the room, leaving her alone. "Now then, what will happen next in the future…speaking of which, I've got to log this in the future…" Da Vinci thought as she sipped on her coffee.

Afterwards, Chaldea's database was updated with new data about the new master of Chaldea, Emiya Shirou…and the reactions were well known for the people that met him.

For Arturia and the others who made the request to Da Vinci, they were thrilled with him being there, although another fight later broke out over who gets to take a nearby vacant room that was near to Shirou's assigned room.

For Irisviel, she was glad that she got to spend more time with her adoptive son.

For Jaguar-Man, she was just glad Shirou was there.

For EMIYA, he just paid no attention to it.

For Gilgamesh…let's just say a portion of Chaldea had to be fixed…

As for Shirou himself…let's see how his first day turns out…

Shirou let out a yawn as he was getting out of bed. Afterwards, he took a short shower before getting dressed for the day. "Hm…Da Vinci told me this uniform is a mystic code…I wonder what properties it has?" he thought as he tried it on along with his red trench coat. As he wore his coat, it was then he noticed his left hand.

On it were command seals, which coincidentally, have the same design as the one in the Fuyuki Grail War. "To think the command seals were the same design as my previous ones…" he thought before he left his room.

As he was walking down one the hallways, he heard whispers from other members of Chaldea passing by.

"Say, that's the new master of Chaldea…"

"Wow. He's such a hottie…"

"I wonder what he could do…"

Shirou let out a small sigh. "I knew this was going to happen…then again, I suppose being a master here is a lot different back at home, where instead of the Church officiating it, paperwork takes its place instead…"

"Oh? I did not expect to see you here, boy."

Upon hearing the voice, he saw Medea. "Caster."

"Looks like the rumors were true. I heard that Saber's old master somehow arrived here and became a master once more." she said as she examined him, slightly creeping Shirou out as she stared at every corner of his body. "And…you seemed to be a lot different the last time I saw you…"

"Um…Caster, can you stop? You're creeping me out…" Shirou said.

"Excuse me. It's just that you seemed quite unrecognizable to me." she said as she gave him some space. "Anyways, it's quite odd of me to say this, but welcome to Chaldea." she said before she left.

"She still hasn't changed…now then, I got to go to the summoning altar." Shirou thought. However, it was then he heard a few noises in the corner. "Hm? What was that?" he thought as he then went over to the corner. As he arrived, he saw a bunch of boxes on the ground along with someone on the ground. "Hey, are you alright? Do you need some help?" he said as he raised a hand.

"Yeah. Thanks for the offer." the person said as he got up grabbing Shirou's hand. As he did, the person immediately recognized him, and the same thing happened to Shirou as well. "You are…Saber's master."

"You're…Assassin."

"Well now, this is quite unexpected. I've never thought to see you in a place like this." he said as he got up. "Not to mention that you became a master again."

"Yeah. So, what were you doing?"

"Oh. I was carrying those boxes earlier."

"I see. Need some help with them?"

"No need. I can handle them, but thanks for the offer." he said as he began to stack the boxes up before continuing to walk. "Anyways, it was nice meeting you again. See you."

"Yeah. Bye." he said as Assassin soon left.

"Even as a master, you're still trying to help people…you haven't changed…" a new voice said.

Shirou turned around to see someone he was not expecting to see. "Waver-sensei?"

Waver let out a small sigh. "Don't call me that, Shirou. You know we're no longer teachers and students. Just call me Waver."

"Okay…"

For a short moment, nothing happened between the two before Waver continued the conversation. "So, I heard. You actually came here by a portal that was connected to another dimension?" he asked.

"Yeah."

Waver let out another sigh. "Why is it that you always find yourself in situations that are considered to be impossible? I swear, no matter wherever you go, trouble always seems to find you. It's like you were cursed or something…"

"I get that…so, how did you get here?"

"Oh, that. Well, I'm a pseudo-servant in this situation, in which said servant happens to be Zhung Liang."

That got Shirou surprised. "A pseudo-servant? What is that?"

Waver let out a grumble while rubbing his head. "Well, to put it short, a servant that has manifested utilizing a human as its vessel."

"I see. Something like a possession?"

"It's not as simple as that." he said as he took a smoke. "Anyways, good luck being a master here, considering that both my sister and Gray are here as well."

"You're kidding me. They're here too?"

"Yup, and they're still the same as ever. Speaking of which…you seemed different from the last time I saw you, and it's not because it's been a long time since I last saw you. It's like…there's something completely unknown inside of you…"

"Well-"

"Shirou-san!"

It was then both men heard a voice and turned their heads towards a direction, which showed Mash coming up towards them. "There you are! I've been looking all over for you! You know that you're going to summon your servant today!"

"Sorry. I've just been catching up with a few people that I know."

"That's fine, but hurry up. Senpai and Da Vinci are waiting, you know."

Shirou nodded. "Sorry, Waver-sensei. We'll finish this another time. Bye!" he said as he left with Mash.

Waver let out a sigh. "He never changes…"

Shirou and Mash arrived at Chaldea's summoning room. As they did, they saw Ritsuka and Da Vinci, who were waiting for him. "You're late!" Da Vinci said with a pout.

"Sorry, I got caught up with a few things." Shirou replied as he looked at the summoning altar in the room. "So, how does the summoning work here? Do I need a catalyst or something? Or do I not need one?"

"Well, those options are available, but in Chaldea, I usually use saint quartz to summon servants." Ritsuka replied.

For a moment, Shirou was a bit confused. "Eh? Saint quartz? What is that?"

"This." Mashu replied as she pulled out some saint quartz for Shirou to use. "In addition to that, you also can get craft essences or mystic codes from the altar too by using them."

At that moment, Shirou could not help but realize one thing after hearing Mashu's explanation. Chaldea's way to summon servants…was gacha. Upon realizing it, he nearly fell down in disbelief. "Are you kidding me?! Chaldea's way of summoning servants sounds exactly like a gacha game mechanic!"

"Um…Shirou-san, are you alright?"

"Huh? Oh, y-yeah. I'm fine." he replied as he began to put the saint quartz on the altar.

It was then at that moment, the altar lit up, temporarily blinding the two from how bright the light was. The saint quartz then disappeared, then formed into multiple blue orbs. Then the blue orbs started to connect with each other and turned into a ring of blue sparks swirling around. Then the ring split into three and continued to swirl around. As the light faded, it revealed a silver card showing a knight holding a sword with both hands. However, the card started to crackle as gold sparks moved around the card, turning it into a gold saber class card.

"So that's how the summoning looks…but what's with the card…?" Shirou thought.

The card then disappeared as a woman appeared. The woman had pink hair held up by a wooden black and red hair clip in a ponytail. She was wearing a low-cut blue and red kimono with wide sleeves that had intricate designs on it. The sleeves were kept shut with a simple clasp that allowed her belly to peak out through the folds. Four katanas were strapped onto her waist and her legs were covered in black stockings that were protected by sturdy red and blue leg armor. She opened her eyes; the color of her hair made her light-blue eyes stand out even more.

"Shinmen Musashi-no-Kami Fujiwara no Harunobubu...!? Sorry, let's do that over! Servant Saber, Shinmen Musashi has arrived!" she exclaimed.

For a moment, nobody said anything as everyone laid eyes on each other. However, one certain master had a few thoughts about the current situation.

"Oh you have got to be kidding me! The servant Shirou summoned was Musashi?! Her of all people?! Oh dear, looks like Shirou is in for a rough ride."

"Musashi? You mean Miyamoto Musashi? Are you telling me that Musashi was a woman? Well then again, this isn't the first time I found out that a famous hero in history was actually a woman, so oddly enough, this did not shock me…" Shirou thought.

Meanwhile, Musashi looked around her before noticing Shirou, staring at him. For a moment, nothing happened, which prompted Shirou to continue the conversation.

"So…you're my servant? Nice to meet you, Musashi." he greeted.

However, instead of a return greeting, Shirou got a different reply the moment she saw him.

"Gramps?!"

"Eh? Gramps? Who are you talking about-?!"

However, before Shirou could say anything more, Musashi immediately jumped towards Shirou, giving him a hug that made both of them fall to the ground. "It's been a while gramps! I missed you!" Musashi exclaimed excitedly.

Meanwhile, Ritsuka, Mashu, and Da Vinci could only look at the scene in shock. "Oh dear…that was unexpected." Da Vinci said.

"Um…senpai? What is this?"

Ritsuka let out a sigh. "The biggest misunderstanding Shirou will have to face…and possibly, a future bloodbath…"