Shintaro knew Ominous Foreshadowing when he heard it-- or didn't hear it, in those moments where Momo would fall silent in the middle of intense bickering instead of snapping back at him, and he knew his head was in danger of meeting the bottom of his trash can.
But he knew the signs. He knew when his mother sighed, he was going to regret what would next emerge from her mouth. He knew that whenever Kano opened his mouth, he was going to be dragged along into something he'd need three days of computer-basking to recover from. He knew in every single scary movie, approaching conflict in a manga or simple scenario, the worst thing a person could say was, "What could possibly go wrong?"
So when his mother ruined his afternoon by announcing that their pregnant neighbor had just gone into labor while her husband wasn't due back from a business trip until late that night, thus ensuring that she (being the kind person that she was) needed to take her to the hospital and remain by her side until her husband could arrive) and summarily, that she needed the two of them to watch the woman's children for some undetermined amount of time, Shintaro was already sweating in his jersey.
He knew what came next, as Momo explained the situation to whichever member of their dysfunctional group had bothered to answer their phone first (and he prayed it was Kido). But even he, without straining to listen, could hear the muffled, all-too-blithe voice of someone who was distinctly Not Kido.
"If you can't come over for group activities, that's no problem! This can be our mission for the day! After all, it's just babysitting, right? What could possibly go wrong?"
"Shit," Shintaro said dully, yanking the phone from Momo's fingers and hanging up. "That bastard's doomed us all."
The laboring mother (and not his own) had two children, a seven-year-old boy who thought the answer to everything was "Kick it", and a four-year-old girl who was only cute when she closed her mouth.
Which, as Shintaro quickly discovered, was never. Even when she was eating, there was rice and vegetables flying everywhere (and Konoha morosely bidding a silent farewell to a chunk of carrot as it shot from her mouth to the floor). Kano wasn't discouraging her open-mouthed habits in the slightest, prompting her to talk about her brother, whether she wanted a baby girl, boy, or dinosaur, and if she wanted to marry Shintaro when she grew up-- a question that threw Ene, snug in his phone in his pocket, into hysterics, from the sound of it.
"Ewwwwww," said the potential bride succinctly, as one-fourth of her omelet oozed a ketchup-y trail down her chin. Hibiya was already reaching for napkin with a long-suffering grimace. He'd have to treat the poor kid to a soda later.
"It'd never happen," Shintaro assured her. "And--" It was about the time he realized that Brat Senior had inexplicably vanished at some point during his fight to get Brat Junior to sit in her chair, along with Momo. Mary and Kido's disappearances were at least explainable; Kido had activated her eye ability the instant the two kids had started a yelling contest and hadn't been seen since, and Mary had tearfully locked herself in the bathroom after the older one had declared her hair his mortal enemy and gone after it with violent exuberance and grabby hands. Seto was likely still trying to coax her out.
This wasn't promising.
"Where did Momo go?"
"Ah... the younger Kisaragi?" Kano chirped. "She said something about trying to distract our other small friend, and off she bravely went! I'm sure she's fi--"
The sudden and incredibly masculine bellowing threw them all into stunned silence, except for their charge, who bleated out a challenging "Ora!" of her own.
"W-what was that??" Hibiya was already glancing around, blanching. "Where did that even come from?!"
Shintaro was already pushing back his chair, but threw a disgruntled "Probably my idiot of a sister" over his shoulder as he left the kitchen. As he did, he heard Kano continue, "... Yep, she's fine. So then, Akane-chan, want to go find the Mysterious Green-Haired Ghost? Revealing her is good luck!"
How Kido hadn't murdered him yet was a question Shintaro pondered daily.
"Hey, Master, do you think he's going to have his left eye bruised when we see him again, or his right?" Ene piped up from his pocket. "I'm now taking bets!"
"Both, if we're lucky."
As he'd suspected, Momo was not at the mercy of a heavily-muscled intruder. She'd found the computer, pulled up an LP of some video game that looked like a bunch of heavily-muscled intruders pummeling each other, and was explaining the premise to a very intrigued-looking kid.
"See, Jotaro's just cool, isn't he? Making that pose right after Star Platinum sends 'em flying, like he doesn't even care!"
The kid's eyes were shining like the rainbow bubbles now floating threateningly about on the screen-- and Shintaro stared, because bubbles were supposed to be screensavers, not a valid method of attacking. "Cool!!"
"Hey. LP fanatic." Shintaro stepped closer, shaking his head when Momo glanced over at him. "You're supposed to be watching him, not giving him more ideas on how to make Mary cry."
His sister glowered at him, abandoning her seat to prop her hands on his hips. "It's keeping him entertained and in one spot, right? And I already told him that it's not okay to pick on girls!"
"Ohhh, I see. Momo-sensei's imparting her wisdom through BL bara posing."
"It is not," Momo began heatedly, but they were both interrupted when Brat Senior pivoted and charged straight at Shintaro with a war cry. Or, to be more specific, with a right hook at Shintaro's crotch.
SUNLIGHT YELLOW OVERDRIVE was one hell of a stupid attack name, he mused, before the pain shoved him to the floor and he could barely hear Momo's panicked voice over his own high-pitched noises and Ene's increasingly-aggravating laughter.
"To be fair, though, Master-- you know, he's been perfectly nice to all the girls while you were sobbing on the ground! Your sister taught him well!"
Ene had finally stopped laughing - sans a snort or two every three minutes or so - but her attempts at placation weren't making Shintaro feel any better. Not even Momo's guilty face helped. The only thing keeping him from losing all faith in humanity was the fact that Kano did indeed look like a panda, thanks to Kido, and she had dragged the rest of the group out the door (with Mary still cringing on Seto's back) with a profound apology to both of the siblings.
That, and the brat duo had finally fallen asleep, with only the sacrifice of Shintaro's shirt to the drool of Brat Junior, leaving him and Momo to collapse on the couch in order to wait for news from the hospital.
"Hey... Oniichan?" Momo's guilt had receded enough for her to pursue a conversation, much to his chagrin. He'd only just started to enjoy the newfound silence.
She was looking at him, frowning thoughtfully. "Do you remember anything? About when we were their age?"
The true answer was that he remembered too much, his baby sister coughing and coughing up salt water and shaking and crying and everyone else crying--
"You were obnoxious."
That much wasn't a lie, and from the way Momo's cheeks puffed up, she knew it.
"You used to follow me everywhere," Shintaro continued. "Calling out for me and crying if I didn't stop and wait for you. It was seriously a pain. But at least you didn't babble half as much as this lady's little girl."
He almost missed being adored.
"She just needs a decent big brother who doesn't watch porn every chance he gets," Momo muttered, and the familial arguing commenced-- albeit quietly, because neither one of them had the energy required for newly-awake children.
She was asleep on his shoulder when Ene reported a phone call, and she didn't stir when he answered it.
"Twins," his mother announced, tiredly. "I'm sure they'll be needing you around more often!"
He wasn't leaving his room for five days.