Luigi gasped and plastered himself to the wall.
"There's somebody in my house," he whispered like a paranoid grandma. "There's somebody in my house!"
"Well I could've told you that," Mappy said unhelpfully. "There's three—I mean, two of us right here," he smirked at the Poltergust, who didn't respond.
"No, I mean there's ANOTHER person! There in the hallway!!" Luigi hissed.
"Luigi, if that was an actual human, as I'm sure it is not, wouldn't that be a good thing??" Mappy asked pointedly.
Luigi frowned emphatically. "Flip no! Humans are scary."
....Case in point
Mappy didn't give up. "But haven't we been spending this whole evening LOOKING for a human?"
"...No one ever said Mario wasn't scary," Luigi said at last.
Mappy crinkled back down into his pocket. "You win. Go throw yourself in the toilet."
Luigi frowned again. "Thanks Mappy. Your support is so appreciated."
So, once again inadequately prepared to embark on his stoopid adventure to save his scary human brother, Luigi and company stepped out into the hallway, anticipating to be ambushed by deadly windmills or something at any second. But what they stoopidly thought was that they could anticipate anything at all.
Because they couldn't.
Right there in the hallway, hovering outside a random door, a tall, hunchbacked ghost that looked like the ugly uncle of Dracula was moaning like one of those 40's crooners, only this guy was probably kicked off the 1800's equivalent of American Idol.

Mansion: For your INFORMATION, it's called Mansion Idol. My name, trademarked. Do not use.

TC#1: Or what?

Mansion: Or I steal your voice box! Why are you people so morbidly curious??

Luigi: Well, that doesn't sound that bad.

Mansion: Indeed, especially when you can't run around needlessly screaming your brother's name all night.

Luigi: ...I take it back!! I need my voice box!!

Then, just because he had to satisfy a random urge, Luigi stood there and screamed at the top of his voice right in the middle of the hall.
"MARIO!!"
Because that's very helpful when you're on a mission like this.
Trust me.
"Idiot!! What is wrong with you??" Mappy hissed.
Count-Creepyhead Dracula Knockoff whirled around, stared at Luigi for about three seconds, and then turned right back to slam on the door he was haunting.
"MELODY!! OPEN UP!! There's a scary human out here with a vacuum and he's wearing lederhosen!!"
Luigi screamed. "WHERE?!"
All at once a disembodied voice filled the hallway, probably the aforementioned Melody. I don't know. I'm making this up as I go.
"Nice try, Shivers, but it'll take more than that to make me look at YOUR face!"
Agitated and clearly still panicking, the sharply-dressed ghost guy, Shivers, turned away and grabbed an extinguished candlestick from the wall. Backing away, he swung it at the scary human like a toddler at tee-ball.
"Stay back demon! I'll concuss you!!"
Luigi tapped his chin and frowned. "You know, these ghosts are actually getting nicer the more I meet."
"Wow, lucky to be you," Mappy remarked as Luigi ducked the brass weapon.
"You're going to pay!! I was this close to getting into Melody's concert!! And you ruined it!!"
The voice from the door yelled again. "No you weren't Shivers, quit flattering yourself!"
Luigi held up the Poltergust's nozzle like a shield as Shivers brought the candlestick down across it like a sword. An epic CLANNNG filled the hallway.
"Yeah Shivers, quit flattering yourself!" Luigi said hastily. Too hastily, because he didn't think about the consequences of that stoopid statement.
With an angry snarl the ghost knocked Luigi backwards, hitting the Poltergust so hard that it momentarily flew from his hands. He fell to the floor.
"Mappy, options!" he demanded.
"Use the fire, ya moron," Mappy replied.
Luigi perked up. "Oh yeah." Grabbing his new flamethrower, he sent a column of flame spewing upwards into Shivers' face like a geyser in springtime.
Or, y'know, like a gruesome display of human torture and indecency.
Whatever triggers the next plot point.
Shockingly to discover, Shivers did not turn into a terrifying pile of ash, because he's a ghost. Somewhat unshockingly, he still shrieked like a banshee gargling saltwater.
"AAAAAAAHHGGAHGAHGAHGAHH!!"
Shivers stumbled back on his nonexistent legs, cowering beneath the light of his now-lit candle. His moan was so pitiful that Luigi actually started to feel a little bit bad.
"Oh, man, are you okay?" he stepped forward, completely ruining the entire ghost-prey relationship.
"Luigi, are you thick?" Mappy asked.
Before anyone could answer that, Shivers held out his burning candlestick and screamed. "AHH!! FIRE! STRANGER DANGER! STRANGER DANGER!!"
Now it was Luigi's turn to frown in stoopidity. "Um, you know candles are meant to burn, right?" he asked.
Shivers was too busy flailing around the burning candle to hear. "IT'S RIGHT ON TOP OF ME!! RUN AWAY!! RUN AWAAAAAAYY!!" With those words of gallantry, the discount vampire turned and floated frantically back down the hall, trying desperately to get away from the burning candle of death in his own hand.
"WOULD YOU PEOPLE QUIET UP YOUR PIEHOLES BEFORE I COME OUT THERE AND STUFF THEM WITH SHEET MUSIC!?" Probably Melody hollered from behind the door.
Luigi wasn't listening to threats this chapter. "Classical or jazz?!"
A loud angry HONK that sounded like a French horn hitting the door was his response.
"Sass doesn't suit you, Luigi," Mappy informed.
Luigi crossed his arms. "Whatever. Should we be concerned about Shivers?"
"What's NOT to be concerned about?"
"Fair point," Luigi said. "He seems like the type who could accidentally burn water."
"I could say the same thing about you," Mappy retorted.
Luigi would have blowtorched him, but remember where Mappy was currently situated.
Instead he said, "As a matter of fact, I just happen to be very competent in the kitchen. I made a cheese soufflé last week that Mario dies for."
There was an awkward pause in the hallway as Mappy had no argument for this factoid.

TC#2: Woah, Luigi is good at things?? I never thought I'd see the day!

Luigi: Oh come on, is that really necessary?!

Toad: Of course he is. He's good at winning by doing absolutely nothing!

E.Gadd: But you could argue that nothing isn't actually being good at something.

Luigi: Not you too!

Author: Don't be upset, Luigi. This book is your chance to prove yourself.

King Boo: *cackles* Beautiful odds.

"Shivers is getting away," Mappy said at last.
Luigi cocked the Poltergust like a rifle. "Oh no he isn't!"
*CUE THE EPIC COP CHASE MUSIC*
And so the ghost who was afraid of fire ran screaming with his candlestick as Luigi chased him down the hallway.
Yep. It's pretty sad, but we've come to this, folks.

Luigi: Hey, I don't think it's sad! I finally feel like I have some semblance of control of the situation!

Mario and King Boo: That's cute.

Luigi: ....I'm not sure how I should take that—

Author: THE BROS ARENT ALLOWED TO TALK!! WE ALREADY ESTABLISHED THIS!! *forces the app to crash* LETS JUST STAY FOCUSED ON THE STORY, PEOPLE!

So Luigi followed the sounds of the gagging hyena down the hall. As he went, disconcertingly random disembodied voices rose up from the walls around him in complaint at this racket.
"OH SHUT UP SHUT UP SHUT UP!! CANT THE DEAD GET ANY SLEEP AROUND HERE?"
"Not with YOU hollerin' like that!"
"THAT was not me, okay??"
"I oughta eat your corpse!"
Luigi gazed in awe around him as this cacophony of sound filled the air. "Wow. I don't think I've ever heard so much paranormal chatter."
"It's getting them to shut up is the hard part," Mansion grumbled.
...
With everyone now thoroughly confused and annoyed, Luigi came to the door at the end of the hallway, which Shivers had seemingly gone through. Unfortunately, it was locked.
"Oh well, looks like it's not gonna work out after all," Luigi shrugged, turning away.
At once Poltergust reared up in his hands like an angry tiger. "Nonsense, that's no way to talk!" he exclaimed. "Luigi! This is your moment! Why, if you were to look within yourself, you might find the answer to your present problem and simultaneously open the door to a whole new world!"
Luigi widened his eyes and looked at his friend in his hands. "Your words inspire me, o vacuum," he said. "You're right! Let's get him!" Feeling as powerful as professional wrestler John Cena, he gathered himself, took a step back, and hurled the entire weight of his shoulder at the door.
THONK. As Luigi lay moaning pathetically on the floor, Mansion chimed in with this great bop to celebrate.

[There should be a GIF or video here. Update the app now to see it.]

"So, what have we learned here?" Mappy asked.
"Doors are jerks," Luigi moaned.
Poltergust seemed surprised. "Luigi, I was getting at the fact that you have a key. Maybe you could try it??"
Luigi sat up. "Oh. Well you could've been more specific."
Mappy groaned as Luigi unlocked it. "Haven't we discussed this before? This whole game would take ten minutes if Luigi could bust down doors. Or magically light the lightbulbs. Like Toad."
Luigi paused as he opened the door, frowning. "Game? What game?"
Fortunately, before the Nintendo Secret Police could sweep in with their blow darts to wipe his mind, he got distracted by the new room he had discovered. And it was
"A dark, smelly laundry room??" Luigi tried to pinch his nose, but since his nose was so big he had to wrap his whole hand around it. "What do they wash in here, ectoplasm?"
"I don't wanna think about it," Mappy replied.
"Luigi! Focus!" Poltergust instructed.
"Yes, mom," he sighed.
There was no sign of Shivers in the tiny room. So Luigi opened a door on his right.
Or rather, it opened and smacked him in the nose.
Fortunately, he already had a hand on his nose, so he got away with only minor wrist paralysis.
"Luigi, quit wasting time," Mappy said.
Luigi, emboldened by pain, snapped back, "How about I put you in the wash and let you think that through again??"
There was another awkward moment of silence (what number is this? I've lost count).
Then Luigi stuck his wrist in his mouth and grabbed Mappy with the other. Then he headed for the washing machine in the corner (the old kind that had one of those wringers on top because hot air hadn't been invented yet).
"Okay Luigi, I was just joking," Mappy said. "I'm sure Poltergust agrees we don't have time for petty arguments!"
The Poltergust, however, had ceased being sentient.

Toad: I realize this must be awkward for you.

Mappy: Well if you ask me, being sentient only sometimes is stoopid!

Poltergust: Well maybe being sentient all the time is a lot of work.

Luigi: Oh boy, I can attest to that!!

Author: Wait... how is Poltergust texting on an app??

TC#1: ...I'm sitting here imagining a vacuum with a touch screen—

OKAY WE HAD A POINT I PROMISE
Luigi opened the washing machine and threw Mappy inside. "You're in time out until I catch Shivers," he said. "If you belittle my efforts one more time, I'm gonna do the grass stain cycle!"
Mappy was not as offended as you thought he'd be.
"...Luigi."
"I just don't see why humans and paper can't get along anymore," Luigi sighed to himself.
"Luigi, I think you should look in here a minute," Mappy called.
"...I mean, we created paper! And does the paper say thank you? ...Well, yes, if it's a thank you note."
"LUIGI!! QUIT YOUR WEIRD BRAIN CONVERSATION AND LOOK AT THIS!!" Mappy hollered.
"WHAT??" Luigi shrieked back, sticking his head into the washing machine.
Random side note, but wouldn't it be fun if we gathered up all the weirdest sentences in the book for an out-of-context extravaganza?
Anyway, as soon as Luigi looked in there he froze. Because right next to Mappy was
"M-M-M-Mario's hat??" Luigi stammered.
DUN DUN WHAAAAAAAAA???!!!
Luigi stuck his arm in, trying to grab the thing at the bottom, but it was too short to reach. So he jumped up on the edge, trying to avoid a rib injury, but ended up tumbling like an idiot into the machine instead.
"Who's in time out now," Mappy remarked from somewhere, voice echoing off the metal interior.
Luigi rolled over and grabbed the hat. "If this wasn't a matter of life and death I'd probably kill you right now."
Then, like any normal person, he promptly smushed the hat in his face and smelled it.
...
"Um... good air?" Mappy asked at length.
"Shh!" Luigi scolded, sniffing. "It's definitely been washed recently... I'm getting a sunny lavender scent. That's a bad sign."
"Why?" Mappy asked.
"Because Mario always uses fresh spaghetti scent detergent," Luigi replied. "He's not even supposed to use a washing machine for hats at all, but being the dodo he is, that's what he likes to do."
"Uh," Mappy commented.
"But yeah, no doubt about it... this is Mario's hat," Luigi added, smelling it again.
"So... what does this mean?" Mappy wanted to know.
"Well, the way I see it, one of two things. Either he hid the hat here on purpose, or the ghosts took it from him and tried to ditch the evidence. Neither of which are good signs."
"Why?"
"Because it means Mario might actually be in a pickle here! We never ran a scenario for that!" Luigi cried.
"Um, what were you expecting? This place isn't exactly World 1-1. Even Mario would be out of his element."
Luigi hugged the hat to his chest and started hyperventilating.
While that was going on, the aforementioned Shivers was still looking desperately around for a way to put out the candle which he seemed physically incapable of putting down. Which is why things were awkward when Luigi's existential moment was interrupted by the ghost opening the lid and slowly, achingly peeking into the laundry machine.
There he found a crumply piece of paper, a red hat, and a green guy with a dorky expression.
"Oh, hello," Mappy said.
Man, I cannot stress how terrifying it is to have someone walk in on you while you're in the washing machine.
"AHHHHHHHHHH!!!" Luigi and Shivers shrieked simultaneously.
"AHHH!" Shivers shot back.
"AH!" Luigi retorted.
"SHUT UPP," Mansion rumbled.
"LEDERHOSEN!!" Shivers screeched. Then he punched the button on the washing machine, which was somehow electric now.
"Wauaagahu!!" Luigi and Mappy were instantly lost in a sea of foam and haunted water.

Luigi: Aw man, that's the second time this month.

E.Gadd: ...

Anyway, struggling like the valiant hero he is, Luigi managed to grab the edge and fight his way out of the machine, hitting the floor like a beached whale. Still covered in soap that made him look like Santa, he got up and glared at Shivers, who had finally put his candle out.
"So this is ghost life? Drive-by rinse cycles??"
Shivers crossed his arms. "No. The rinse cycle doesn't start for 5 minutes."
Luigi stood there and blinked at him for 23 seconds, stoopefied by this information. Then he said, "I'm here to revoke your ghost license."
Shivers snorted. "I'm not a ghost."
Luigi crossed his arms too. "And I'm not an American avocado," he said with straight face.
Shivers blinked. "That makes no sense."
"Just like your statement," Luigi replied. "So if you're not a ghost, then what are you, Shiv?"
"I am not a shiv either! I am the master's head butler!! And my mission is to find his will and exploit all his goods before I die!!"
Luigi blinked for the 6349th time this fic, looked Shivers up and down, and then reached for the Poltergust.
"I'M NOT FINISHED!!" Shivers hollered. "I don't suppose you know what it's like to be treated like an outcast nobody in a post-Victorian society that requires a man to WORK every day of his life for a living!"
Luigi rubbed his chin. "Uhhhh... Well if you mention it—
"AND then, I bet you have no CONCEPT of what it's like to meet the most enchanting woman of your dreams, who makes you feel like love is good and you enjoy being alive, only to be told by said woman that YOU have halitosis!!"
Luigi pointed. "You mean the French horn music lady?"
"YES THE MUSIC LADY!! AKA Melody Pianissima, AKA my girlfriend who doesn't know it yet, AKA the one whose door is perpetually closed, always rejecting, always alluring! How I passionately burn for her, and yet—!"
Luigi cleared his throat. "Let me guess, you've never actually talked to her face, have you?"
"Well... you've never actually talked to a woman either, have you!"
Luigi backed off.
"AND THEN after bowing and scraping to a master—the REAL one with halitosis—for 50 long years, what reward do I get?"
Luigi was cautious. "...A lifetime supply of—
"A LIFETIME SUPPLY OF TOILET PAPER!!" Shivers shrieked, opening the door on his left and revealing a wall of fresh, clean 'white gold', tumbling out of what was once his bedroom.
Luigi stared in confusion and wonderment at the sight.
"...MY LIFETIME SUPPLY!! I KNEW IT WAS HERE!!" he screamed.

Toad: Wait, so there was actually an entire room filled to the ceiling with toilet paper?

Taboo: Previously called the Buttler's Room.

Mappy: ...

Shivers wasn't listening. "Newsflash, peasant! No one needs that much toilet tissue when they're as old as I am!!"
Luigi frowned. "Do you need any? Because I mean. You don't even have a—
"I don't even have a share in my master's will!" Shivers ranted to himself.
Luigi kept frowning. "Yeah, but do you need any? Because what good is money when you're already dead?"
The ghost suddenly stopped very seriously and turned on him. "There's only one person in this room who's already dead, boy, and it isn't me."
Luigi turned in a circle, not understanding.
Shivers' eyes turned red. "Omae wa mou shindeiru."