You give a subtle nod to Shirou and he tells Issei, "Sure, I'd love to help out. What do you need me to do?"
"Oh nothing really," Issei replies, "Just some extra work that's needed at the school; c'mon, I'll explain more about it when we get there".
So now the three of you start walking towards the school; three because Rider went incorporeal the moment she heard Issei coming. Probably a good idea all things considered and you probably should've done the same thing too, but fuck that shit. You were a 'people' person, hiding away when you could be smooth talking and chatting them up for information simply wasn't your style. Besides, second shot at life here; wasting it away doing fuck all isn't appealing to you in the slightest.
While walking, you actually take a moment to think more about Shinji's 'grandfather'; reamains in shade/darkness, generally a sadistic asshole going by what Shinji says, and uses worms of all things. The cogs in your brain are turning as you try to figure out just what's nagging you about this. C'mon, c'mon; what is it....what is it...?
Then it hits you, an obscure brand of evil you've heard of in your travels; the Worm that Walks. A sorcerer or wizard who abandons their orignal body and replaces it with a host of maggots; a dark and vile ritual which is a desperate grab at immortality, at the cost of human morality and sanity. While it grants said immortality and a host of other powers; it robs a man of everything that makes them human. Not to mention just what is necessary to perform the ritual; it's not as bad as the one to become a lich, but it's real damn close.
However...that's how it was back home; you don't know what it's meant to be here. Shirou's inability to cast a simple cantrip, this whole ritual, Lancer's runes, even repairing the armor and Rider's eyemask; all of these were different from how they worked back home, and it was only your own experience and knowledge in spellcraft that allowed you to scrape by. It was like translating Drow Undercommon with standard Elvish; sure they used the same alphabet and had some similarities, but they're different enough to make it difficult to translate from one to the other. Which means you can't be certain that the grandfather's actually evil; a total prick and asshole sure, given what you've heard of him, but nothing that screams 'evil'.
Just to be safe though, you cast Detect Magic on Shirou to check if the worm he swallowed is safe; you're pretty sure Shirou doesn't want a wrinkly old man inside him. And....nope, he's clear; looks like the worm dissolved once it did it's job. That's a relief, Shirou does not have a wriggling, throbbing, elderly man's worm trying to penetrate anything important from within. And holy crap will the innuendo and jokes never end!? God dammit brain, for once you don't want it to immediately make a joke out of everything; especially not this.
Thankfully, Shirou's ambigiously gay friend cuts into your soliloquy, "So...who exactly are you? And why are you here with Shirou?"
"Name's Tandem; friend of Shirou's father, here on business. Though I'd help out," you notice that you've reached the school by now, "So Issei, where do you live?"
"Ryuudo Temple," he narrows his eyes and asks suspiciously, "Why?"
Whelp, time for you to pull out your SOP; "Oh, well, it's just that Shirou's father and I were very close; and now that I've finally gotten in contact with his son I feel a sort of...bond, you know? Like I'm his uncle or something; I would've been here to be with him sooner but alas, work is a fickle bitch. Especially when it involves govenment and the more 'hush-hush, top secret' aspects of it."
"I see..." Issei's face is neutral, but he seems to have bought it, "So you work for the government then; which one?"
"American, Kerry and I'd be on the same job given to us by our different employers; and we hit it off fairly well. Unfortunately; he didn't quite get out of the business fast enough like he wanted. Rounded up several enemies if you catch my drift; had to go into hiding. Couldn't even find him until recently." Then you decide to switch tracks, "So, what do you need us to do?"
"Oh not much, just some stuff down in the basement and some wiring; it'd be easier for me to just show you when you're there." A lie; the tell was barely there, a slight twitch, but it was a tell nonetheless.
Time to press further, "So...anything interesting happen at this temple of yours recently? Any big 'religious revelations' for all you monks?"
"Actually yes," he perks up and ecstatically explains further, "A woman came to the temple several days ago, and she's given us all several different viewpoints on religion as a whole. It was all rather...enlightening, showed us what mankind's real place in the world is..."
Warning bells were ringing in your head now, and you were alert and ready to attack at a moment's notice. You were about to question Issei further, but he announced, "Well, here we are Emiya."
You all entered the basement, and you and Shirou were horrified. The basement was covered in runes and candles; the middle of the room held a circle drawn in blood and in altar in the center. several corpse were strung on the walls; and simply looking at the room was painful, sending a message to the mind that 'this is not for man to comprehend'. You've been in cultist bases before, but this one takes the cake; it's like every inch of it was trying to rend your mind asunder with alien, incomprehensible forces that are beyond the understanding of mortals.
"I-Issei; what the hell?!" Oh man, Shirou...this was his friend... "What....what have you done...."
"She taught us much, Emiya; of the real nature of the world," the cultist giggles, "Of the true makers of the world, of the worthlessness of our pitiful existence. Of what awaits us, and the world in the end..."
The hysterical giggling become full blown manic laughter now, "She has shown us the temples of R'lyeh! The visages of their caretakers and crafters! The true forms the the gods that have made us! She gave us the enlightenment we have all been seeking..."
"And in doing so, we were reborn; now we go forth and act in the will of our master: Nyarlathotep. And he has demanded your deaths!" Issei then pulls out a ceremonial dagger and stabs himself, ripping it across his stomach and up through his heart and throat in a macabre mockery of seppuku.
As his blood spilled onto the floor and his body dropped lifelessly, the ritual circil began to glow with an unearthly light. The other corpses began to bulge and rip, as unholy terrors used them as a portal to this world. Several beings that seemed to be made of tar and eyes came out; their bodies warping and changing to their inhuman wills. Issei's own body began to rise, as it was slowly being changed by eldrich energies flowing into it from the altar and circle. You don't know what it'd doing, but it can't possibly be good.
Rider's now out of hiding and beside you, ready to fight. Shirou's still shaken, but has grabbed a pipe to fight back with. As for you? Your Rapier's in one hand and a Sword of the Planes is in the other, ready to tear into these things.
What do you do?
[X] Write-in (tactics, plans, etc.)