I've been researching the game Dungeons and Dragons for a potential attempt at playing it, and ran across the info which spawned this little cracky idea. With apologies for the title; someone on a message board referred to the process of invoking the summoning meme as "hasturbating", and I'm looking for opportunities to use the word. Technically I think the Cthulhu Mythos, including Hastur, were only in First Edition D&D. Also, as Wensley points out, the actual D&D rule is that every time Hastur's name is spoken, there's a 25% chance he'll send byakhee (giant zombie bird things) to attack, and if they're killed, there's a 25% chance he'll show up himself. Somehow this has gotten mutated in popular culture into the instant summons, which I can imagine Ligur mocking him over regularly. But since this is Adam's campaign, he can houserule in whatever the heck he likes. The idea of Adam telling the Them about his infernal ancestry was kind of borrowed from Igorina.
"Congratulations, the battle is won!"
The Them cheered and applauded; Adam ran a really good campaign.
"Ding dong, the witch is dead!" sang Brian, punching the air.
"Wasn't a witch, she was a hag," Wensleydale corrected him. "'S different in this game."
"Whatever. Where's the treasure?" Brian bounced excitedly.
Adam ruffled through some papers behind the Dungeon Master's screen. "Okay, there are treasure chests here, and here, and here ..." He put the markers in the right places on the map. "And some piles of stuff here and here. Prob'ly should be checking for traps, Brian. Wensley, have you got Detect Magic? And you all should make some Search checks in case you're missin' anything."
"Got it." Brian rolled the dice appropriately as his rogue disabled traps and picked locks, and Wensleydale's wizard helped him with the magical traps. Pepper's barbarian assisted them by smashing a couple of boxes open when she got tired of waiting. The imaginary treasure spilled out across the imaginary floor, ripe for the taking.
"Okay, along with all the gold and stuff you find three scrolls ..." Adam handed over three carefully teastained and rolled papers. He enjoyed making props. Wensley immediately claimed the scrolls and started to look through them.
"Ooh, a Teleport scroll! Better save that one ... This one doesn't look magic, but I can't read the language ..."
"Aha! Sequel hook!" Pepper took the scroll and glanced over it, then placed it with her other "equipment" props. "We should get that translated when we get back to the city."
"Yeah ... well, this one's just stupid." Wensley showed the offending scroll to the others, who squinted at it. "What's the point of a scroll that just says 'HASTUR HASTUR HASTUR' over and over?"
Suddenly, Adam's room was filled with a cloud of vile-smelling black smoke which set the Them coughing uncontrollably. From within the smoke, they caught brief glimpses of something horrible. Being thirteen years old and already somewhat used to the supernatural, they reacted with much less running and screaming than adults would; Pepper grabbed for the prop greatsword she'd made from a broomhandle, while Wensleydale and Brian gasped "Cool!" Dog woke up and yapped angrily at the intruder.
As the smoke cleared, the monstrosity reshaped itself into something almost human; to be precise, a tall sharp-featured man in a soot-stained suit, looking vaguely puzzled and still clutching a pencil. It blinked and peered about in confusion before realising where it was and drawing itself up. Its eyes glowed red and its teeth lengthened, and a sickly red glow arose around it.
"Cower, mortal whelps, before the might of the Inferno-"
"Yeah, you're not scaring us," said Adam drily.
"Eh? Oh, forgive me, Your Royal Lowness!" The demon bowed, losing a lot of the infernal glow. "Pardon the interruption."
"'Sokay, no need for all the bowin' and such. You know I don't like that."
The Them stared in bafflement at Adam. Not so much because of the Antichrist thing; he'd restored their memories and explained that to them after they started to notice weird things happening around him and demanded an explanation, and he'd decided it was safer to let them know what they were up against in case of future apocalypses. This, however, was quite a lot weirder than even the usual things which happened around Adam, at least in public.
"Oh, sorry. This is Duke Hastur – he works for my, er, other dad, y'know." Adam looked embarrassed. "Sorry, didn't realise the summoning would work on you."
"Wait ..." Wensleydale tried to peer behind the DM screen and earned himself a glare from the other players; some things just weren't done even if you were accidentally summoning demons. "Now you mention that, I remember it, but I thought it said that saying Hastur's name just means there's a chance of monsters appearing and if you kill 'em that's when he turns up. Ah, there, see? 'S in the rules." He pointed at the stat sheet in question.
"Yeah, that's popular culture for you," said Hastur with a shrug. "Most people don't know the exact rules, and it seems to have got a bit muddled, and, well ... since the boss's son is here I reckon it's okay if I tell you demon summoning owes a lot more to what humans expect to work than we like to think about. Stupid, if you ask me. Who am I, Bloody Mary? Uh, look, Your Lowness, if there's nothing important going on, I was in the middle of a meeting, so ..."
"Oh, sure, go on," said Adam, waving his hand dismissively. Hastur vanished in another puff of brimstone-smelling smoke.
Pepper sighed and shook her head. "Poor bloke."
"He's a demon, we don't have to be nice to him – er, no offense, Adam."
"None taken, Brian, it's okay."
"Yeah, but it must be a right pain, having to drop whatever you're doing and appear just because someone says 'Hastur Hastur Hastur'-"
Hastur blinked in a surprised manner most unbecoming of a high-ranking demon. "What?"
"Whoops. Sorry, that was me," Pepper said, raising a hand in embarrassment.
"Right. Well, uh, don't do it again," Hastur said, cowed slightly by Adam's glare, which clearly read Don't even think about hurting her. He disappeared again with another puff of smoke.
"Can we stop summoning him?" Wensley coughed. "I don't think all this smoke is good for us."
Adam waved his hand and the smoke disappeared. "Sorry 'bout that. Let's get back to the game."
Brian grinned. "You know, it's a good thing demons don't need to take baths or somethin', 'cos it'd really be awkward if he was in the bath when someone said 'Hastur Hastur Hastur' an'-"
"Will you stop that?"
"I wanted a turn!" Brian protested.
"I don't have time for this! Er, 'scuse me, Your Lowness, but I really don't think-"
"'Salright, we're sorry. You can go, I'll call you if the Apocalypse starts again." Adam nodded politely. Hastur dematerialised again with an angry-sounding poof. The rest of the Them giggled.
Adam raised a hand. "Okay, now I really think we should all stop saying 'Hastur Hastur Hastur' – aw, now you got me doing it-"
"Oh, now you're just milking it!"
"Sorry," said Adam, grinning in a way that suggested he really wasn't. Even the powers of Hell cannot stand up to a quartet of thirteen-year-olds who've just discovered a new way to annoy an adult who can't stop them. Hastur pressed his forehead against the wall and groaned.
"Look, Mister," Brian suggested reasonably, "I reckon that if you stay here, we can't technic'ly 'summon' you any more."
"Hey, yeah, that's true," mused Adam. Hastur looked back up at the group to see Adam proffering a blank character sheet and a handful of dice with an ingratiating smile. "Wanna play?"
Hastur sighed. "... Yeah, alright. Scootch over, four-eyes." With that, Hastur flopped on the floor between Wensley and Adam, and started flicking through the Player's Handbook. "So how d'you play this again ...?"