Yo! Back with another story. This is something that I've wanted to do for a while. A triple crossover! After a week of planning and outlining I've finally finished the first chapter. Really hope you all come to enjoy what I have planned!

I also invite you to join AizenTheGoat's discord server, had a few writers help me out and I really appreciate it. If you want to get help with a fic or just talk with fellow readers and writers about anything then this is the place for you.

Link - YkhXEeFzKT

EDIT APRIL 27: So as you all can tell I rewrote the first chapter, my excitement got the better of me and I ended up publishing a chapter that I was not happy with and I apologize for that. Here's hoping what I've added will make up for it and make it better.

Disclaimer: I do not own Naruto, Highschool DxD or Fate

"Naruto! Wake up already!" Rin barged through the door and ripped off his blankets.

The blond mage groaned in annoyance as he was exposed to the cold, curling himself up in a ball.

"That's why I tell you to at least wear some shorts. Honestly, why do you never listen to me?" Rin sighed in exasperation.

"I'll be doing enough of that when we get married, might as well enjoy my freedom while I can." He mumbled.

Rin scoffed, "Stop being so dramatic, if I can't get you to listen to me now then I have no hope I can do otherwise once we are married. Now get up please."

"What's the point of going to school anyway? Once you get into the Mage's Association we're gonna fly off to London. Thankfully as your husband they won't be able to kick me out." He yawned as he sat up.

"That's if the Association even invites me... It's always good to have a backup plan." She told him as she threw him his school clothes from their shared closet.

"You always were the more reasonable one of the two of us." He smiled as he began changing.

"Of course I am." She smiled smugly, "Now stop talking and change. If you're not out in five minutes I'll leave without you."

"You got it boss." He gave her a thumbs up as she left the room.

As he was changing his attention was grabbed by the sight of seals forming on his hand, "Hmm, I know Kirei said the war would be starting early compared to previous ones but I wasn't expecting this just yet…"

"Naruto, final warning!"

"I thought you already gave me my final warning when you left me to change!" He called back with a cackle.

He smiled to himself as he heard his fiancée's grumbling in the living room.

"Well I lied okay? I'm obviously not going to allow you to walk to school alone, I know there are definitely some school girls waiting for the chance to catch you alone and I'm not letting them." She crossed her arm in annoyance as he made his way down the stairs.

"You're adorable when you're jealous."

"I'm not jealous…" She pouted.

"Riiiiight… Anyway, my command seals just showed up." He showed her the back of his palm.

"Hmmm… We'll mine haven't so I suppose we still have some time before the war begins. Will you be summoning a servant soon?"

He nodded, "I don't wanna do it just before the fighting starts, I want to get to know her to improve our chances of winning."

"Sometimes you make me regret the fact that I don't have a catalyst."

Naruto took her hands and held them lovingly, "Don't worry yourself with that. You're an amazing mage and I know you'll get a powerful servant."

"You sound like you're hoping I get a strong servant." She chuckled.

"Of course I am! I don't just want to breeze through the whole thing, the challenge will be half the fun after all." He smiled, "Enough of that now, why don't we get going then?"

Homurahara Academy…

Naruto suppressed his laughter as he watched Shinji being told off by Rin.

"Honestly Shinji, it surprises me how you still try to hit on Rin." Naruto smiled as he placed his hand on the Matou's shoulder.

"N-Naruto… I wasn't aware you were accompanying Rin to school today." Shinji laughed nervously, unaware that he had listened to his attempts to invite Rin to archery practice.

"Our clocks were a bit off today so she ended up waking us up early. A shame since I was having such a nice sleep. Anyway, your persistence is commendable."

"R-Really?"

"It's what I would say if Rin wasn't my fiancee, and while it has been fun to watch your pathetic attempts for a while, it's starting to piss me off as of late." He said as he gripped the boy's shoulder tighter, "I would suggest you lay off from now on."

Shinji winced as he nodded slowly, "O-Of course, not a problem."

"And honestly, inviting her to watch the archery club? She's never seen a single one of your practices, why not think of anything else?"

"Well, I—"

"That was rhetorical you moron, have yourself a nice morning." He patted his back before following Rin.

As he turned the corner of the stairs he caught Shirou saying, "I didn't know you came to school this early."

Rin didn't seem to acknowledge the comment as she continued walking and Naruto turned to see Issei and Shirou fixing some school equipment.

Shirou slowly turned to see Naruto staring at him, "Good morning, Naruto."

The blond didn't say a word, opting to stare straight into his eyes.

Issei felt uneasy as he looked between the two students. Naruto and Shirou never really spoke to each other but the blond had never looked at the other boy like he was at the moment.

With such visibly restrained hatred.

Naruto nodded curtly before he walked off to the direction that Rin had left.

"I hope you got through Shinji's thick skull." She sighed in annoyance as he caught up to her.

Naruto laughed, "Probably did since I scare him shitless. Unfortunately, we'll have to see him when we go to Kuoh later today."

"Please don't remind me."

"Maybe it won't be so bad?"

Later that day in Kuoh, 10 km west of Fuyuki City...

"We really appreciate that three of the four major families have decided to agree to this visit." The Gremory heiress smiled as she looked at the three teenagers sitting in front of her.

"Not like we have a choice." The Matou boy sneered at the Devils in the room.

Naruto sighed, "We just got here..."

"Right..." Rias hid her annoyance behind a smile, "We've come to understand that the Holy Grail war will be starting significantly earlier compared to previous years from what the overseer has told us."

"And you wanted to know why it's beginning 50 years earlier?" Rin asked.

Rias nodded, "If it isn't too much to ask. After all, we haven't exactly made the preparations to make sure no other supernatural race interferes in this yet."

The Uzumaki and Tohsaka heads looked at each other, while the Matou boy looked disinterested and opted to ogle at the girls.

"Well, if Kirei didn't see a need to tell you this information then I see no reason why we should either." Naruto shrugged.

"Okay... Akeno, why don't you prepare some tea for our guests?"

"Of course."

"I'm sorry but I'm really confused, who are these guys?" Issei turned to Koneko with a creased brow.

The white-haired girl didn't say a thing and motioned for him to remain quiet.

Rin sighed, "It seems that Devils have been getting more lax in educating their servants."

Issei frowned and moved himself in front of Rias, "Hey! I don't know who you think you are but don't disrespect Rias like that! She's an amazing King!"

Shinji sat up in annoyance, "Filthy Devil! How dare you speak to—"

"Rin is a big girl Shinji, she doesn't need you to come to her defence." Naruto waved for him to sit back down, "Besides, the Devil didn't do anything to insult her. Are you insulted, Rin?"

"A bit miffed is all."

Naruto smiled as he looked back Rias, "I like to think I'm fairly reasonable and I think it's fair to say that he really shouldn't be here if he's still this unaware of the supernatural world."

"Maybe one of you could tell me since you seem to think you're so much better than us." Issei rolled his eyes

Shinji smirked as he sat back down, "We belong to some rather prestigious families in the mage community Devil boy. We also own Fuyuki and Kuoh, of course no ordinary person knows that."

Issei looked confused, "I thought Rias and Sona were in control of this territory?"

Akeno chimed in as she set down tea for their guests, "Not exactly, it'd be more akin to someone letting you live in their guest room while you pay rent."

"Except that we don't charge rent. We just leave you to your own devices and check-in on occasion just to make sure you haven't destroyed the place." Naruto added.

"But why exactly?"

"We're not here for a history lesson, all you need to do is make sure there will be no interference in the coming month." Rin sat up, "With that out of the way, I bid you all a good afternoon."

"I'm gonna stay a little while longer, Rin. Wait for outside, I'll be there in a minute." Naruto told her as he sipped on his tea.

Rin nodded as she left the club room with Shinji following suit, not bothering to say another word to the Devils.

"They didn't even drink my tea." Akeno hummed.

"I'm not much of a tea person but this is very nice I must admit."

"So, why exactly are you still here? Is there something else you wish to speak about?" Rias asked.

"Right, I just wanted to tell you that I'll be performing my summoning tonight in Kuoh."

"Oh, you will?"

"Yep, just wanted to let you know so that you aren't caught off guard when I do it. Please do tell the Sitri girl this too since she isn't here at the moment."

"Of course, thank you for informing us."

Naruto nodded, gulped down his tea before grabbing the wrapped catalyst and leaving the room.

"I don't like those guys..." Issei muttered as soon as Naruto was out of hearing range.

Outside of the club building Rin was tapping her foot impatiently, "I still don't see the point of this meeting, it's a waste of everyone's time when Kirei could have simply done this over the phone. He is the overseer after all, he should be doing his job properly."

"Simple formalities, I guess it's so that the truce between us and the Devils doesn't come across as fragile."

"I still think Kirei made us come here to annoy us." Rin huffed, "What did you tell them anyway?"

"Oh, I'll be doing my summoning tonight here. Giving them a warning about it so they don't freak out."

"Hmm, do you want me to be there when you do it?"

"It's fine, get some rest instead."

"Okay then." She nodded hesitantly, "Try not to get in trouble okay?"

"I'll be careful." He smiled and pecked her lips.

Later that night...

"This looks like a good spot..." Naruto nodded to himself as he looked around in the dark at the empty park.

"Well hello there~..." The sweet and sickly voice of a woman called out from the darkness behind him.

"Hm? What're you doing out so late, it's a dangerous place you know?" Naruto said as he turned to the sound of the voice.

The woman giggled, "Funny you say that... I was just about to tell you the same thing. You haven't heard of people disappearing around here?"

"Oh I have, I'm just not particularly worried about it." Naruto shrugged.

The woman hummed, "Well you really should be... It's a shame that I have to kill such a handsome young man like yourself. I'll definitely have some fun with your dead corpse before I eat you though."

Naruto looked at the woman emerging from the shadows with an expression of boredom before cringing as he stared below her torso, "What the fuck is wrong with your body woman? How the hell do you get people to follow you looking like that?"

The woman cackled, "A dead man doesn't need to concern himself with such things."

Naruto smiled, "Well, I will admit that I am happy that you've showed up..."

"Oh? And why's that?"

"Well, I was going to kill some chickens to use as a blood sacrifice but now I'll just use you. It would be a waste of chickens otherwise and I don't particularly want to go out and buy any."

The Devil looked slightly taken back at his calmness before smiling madly again, "I have to say, you're really amusing for a human."

Naruto rolled his eyes as he pointed his index finger between the woman's eyes, "Well, you're not amusing me so I think I've wasted enough time talking to you."

"Have you? And what exactly are you gonna do?" She sneered mockingly.

"Finn Shot." He whispered and the Devil woman watched as a red beam of highly condensed magical energy shot out, penetrating her skull and instantly killing her.

Naruto looked at the Devil's corpse and sighed, "This is probably too much blood... I suppose I can have Kirei get this cleaned up."

After a few minutes of meticulously drawing the summoning circle needed for the ritual, he stood up and picked up the catalyst he had set down when he first arrived to the park.

One of the copies of the weapon belonging to the warrior-queen Scáthatch, Gáe Bolg Alternative.

With a smile on his face he placed the catalyst at the center of the circle before taking a few steps back.

He gulped as he took out a mask from his jacket, with a determined breath he placed it on his face.

Shaking off the pain from the mask clasping tightly onto his skin he raised his arm and began to chant.

"Let silver and steel be essence. Let stone and the archduke of contracts be the foundation. Let red be the colour I pay tribute to. Let rise a wall against the wind that shall fall. Let the four cardinal gates close. Let the three-forked road from the crown reaching unto the Kingdom rotate. I shall declare here. Your body shall serve under me. My fate shall be with your sword. Submit to the beckoning of the Holy Grail. If you will submit to this will and this reason... Then answer! An oath shall be sworn here! I shall attain all virtues of all Heaven. I shall have dominion over all evils of all Hell! From the Seventh Heaven, attended to by three great words of power, come forth from the ring of restraint, Protector of the Balance!"

A white light shone as he uttered the last words, lighting everything around him. He stumbled back slightly as he shielded his eyes, only a few seconds later did he bring his arms down to gaze at his servant.

He stared at the woman's long purple hair before shifting to her striking red eyes as she looked at her surroundings before his eyes set themselves on the weapon in her hands.

"The original Gáe Bolg Alternative." He muttered.

Scáthatch looked down at the copy of her weapon laying in front of her feet before turning to the young man, "You... summoned me here?"

Naruto struggled slightly to remove the mask before nodding enthusiastically as he huffed, the strain of the summoning making itself known on his body, "I did! I won't lie, I wasn't too sure if even using a copy of Alternative as a catalyst was going to be enough to summon you considering you're still alive in the Reverse World but it seems that the circuit mask certainly helped!"

"That's right, you shouldn't be able to summon me here, not even with this as a catalyst. Which could only mean... What exactly would be your wish should you obtain the Holy Grail?" Her red eyes looked at him with curiosity.

"To bring back the Age of the Gods. It's something I've been fascinated with since I was a child. I never was as interested in reaching the Root like my parents were... Besides, magecraft was closest to being true magic during this time, wouldn't it make more sense to bring it back rather than risk disappearing in the Root or taking the wrong route trying to reach true magic?"

"So you simply wish to do this for your amusement?"

"Not at all! I have more plans after that but I can't get ahead of myself can I? It's good to be confident but I can't risk getting cocky when the war isn't starting for another month."

"A month? Why summon me so early?"

"I thought it best that we get to know each other before the fighting breaks out, it'd be a lot harder to trust each other if we just met even if we are partners for this war."

"Very sensible thinking." Scáthatch nodded in approval, a small smile forming behind her mask.

"Thank you! By the way... Any idea on how I was able to summon you? Since you can see into the future perhaps it's something we'll learn later?"

"I'm not a fan of using my clairvoyance, the last time I did..." She trailed off for a second, before looking back at him, "I have to ask, what would you have done had you not summoned me?"

Naruto laughed in embarrassment, "Well, I didn't really have a backup plan unfortunately. I would've simply not used a catalyst and hoped I didn't get the short end of the stick."

"Hmm and what exactly was that masked you used? It seems to have taken a toll on your body."

"Ah, it's a mask created by my family. It temporarily increases the amount of magic circuits a mage has and makes them stronger too, it took a toll on me because I've never used it before and it took a lot of magical energy to bring you. I hope I don't have to use it too much in the future since overusing it damages a person's magic circuits."

Their conversation was cut short when a magic circle appeared a few feet away from them. Naruto looked at the symbol in the middle, a crimson rose encased in a circle, and instantly recognized it as the symbol of the Gremory clan.

"Rias! What can I do for you on this fine night? I didn't think you would show considering I did tell you what I was doing."

"Yes, I'm aware... The output of energy from you doing this made quite nervous and I was worried you had gone out to do something else."

"Oh, so you suggest that I would lie to you about this? You wound me." He said in mock-hurt, "Ironic, don't you think? Considering what you Devils did in the third war."

Rias went silent for a moment as she moved her gaze to Scáthatch, "Does your fiancée know you're out here? With such a beautiful woman too?"

Naruto snorted, "Why don't you keep yourself concerned with your own fiancé?"

"So is your business here settled?" Rias asked in annoyance.

"For now, yeah. You wouldn't mind getting rid of that stray's body would you?" He asked, pointing at the dead body.

Rias stared at the butchered body for a second before disintegrating it.

"I do apologize for the mess but you should be thanking me for getting rid of that thing." Naruto told her as he picked at his hands stained with dry blood, "I would say I am shocked that you allowed it to live for so long but you are a Devil so I doubt you care too much about the humans it killed."

"That isn't—."

"Yeah, spare me your excuses. I'll see you some other time I suppose."

Rias clenched her teeth before teleporting away.

"You did a great job of getting under her skin."

"It was rather entertaining. I do hope that there weren't any other supernatural beings around to sense the summoning..."

"Why not do it somewhere where there are no people around then?"

"I needed something to sacrifice and I thought to myself that it'd at least be much better to kill a stray over a couple of chickens. Unfortunately no supernatural beings dare to settle down in Fuyuki, except during the war even though they're always brutally murdered during it so I couldn't do it there even if I wanted to." Naruto chuckled.

"I cannot wait, the thought of battling some of the strongest warriors in history is an exciting one!"

Naruto chuckled, "I guess the texts that said you enjoy battle weren't lying."

"When the Age of Gods ended I had lost hope that I would ever achieve the thrill of battle again so I'm a thankful to be given this opportunity by you."

"Bah! No need to thank me." He looked down sheepishly, "Let's do our best to win the Grail!"

Scáthatch smiled and nodded.

"I have a feeling I already know this but I need to ask, what wish do you wanted to be granted by the Grail?"

"I simple wish to find someone strong enough to bring about my death." She told him as she stared straight into his eyes.

He nodded slowly and extended his hand towards her, "Then I promise you that we will win the battles to come so that you may find the peace you crave and if it comes to this then I will kill you myself."

Scáthatch looked at his determined gaze before nodding and taking his hand with a firm grasp, "I'm glad to hear it, Master."

"While I'm sure you'd love for us to go out and find an opponent for you, it's rather late so I'd like to show you where you will be staying if you don't mind."

"Not at all, master. While I am confident in my abilities it would be unwise for us to pick a fight while you are recovering from summoning me."

"Am I that obvious?" He chuckled tiredly.

"You shouldn't be forcing yourself to act like you're fine if you aren't, sit down and rest."

"I'm pretty sure if I sit down I'll pass out."

"Then we best get you to your home."

"Yeah, that's a good idea..." Naruto looked down tiredly before falling back as he passed out.

Scáthach quickly moved to catch her unconscious master and smiled at his sleeping face, "I look forward to the day you bring me eternal rest, Naruto."

And there's that, hope you all liked what I added to the chapter!