Shikamaru's Bad Day
Three months after Naruto becomes Hokage
"Naruto, how many times has everyone told you not to mess with Fūinjutsu?" Shikamaru cried as he opened the door to the Hokage office and found the Uzumaki slamming his hand down on a seal, face spotted with sealing ink. For a long second, nothing happened. Naruto pumped more chakra into the seal and Shikamaru approached, curious. As soon as he leaned over to fruitlessly try to decipher the seal, it exploded in their faces, throwing them backwards. Shikamaru felt his head hit the floor with more force than one of Sakura's punches. When he managed to blink open his eyes, he found Naruto's face uncomfortably close to his own.
"I think I really screwed up this time," Naruto said as Shikamaru pushed him to a more acceptable distance.
"You made a seal that does who knows what without supervision, probably overloaded it with chakra, knocked me out, kami knows what else, and only now you admit to screwing up?"
"It's worse," Naruto whined.
"How did I get roped into keeping you in line? Troublesome," Shikamaru muttered, rubbing his face as Naruto hovered beside him. "What did you do this time?"
"I think I released the Kyuubi," Naruto deadpanned.
"Troublesome," Shikamaru said before he realized Naruto would never joke about something so serious. Rubbing his ears, the Nara realized the distant roaring was not the lingering aftereffects of a concussion. "Everyone knows you're stupid, but I really don't think you're too stupid to die. Jinchuurikis die without their Bijū sealed inside of them." The lazy man fell backwards into Naruto's chair, nursing his ringing head.
"Before you woke up, I went into sage mode to try and find him. He's outside the village and with—"
"Let's just go find the damn fox and figure out what you did." Shikamaru stood abruptly, grabbed Naruto by the collar like a naughty puppy, and then pushed him towards the window. A loud pop and the Kyuubi's chakra completely overwhelmed their senses.
"He's attacking the village!" Naruto cried and raced out the window.
"Troublesome," Shikamaru grumbled as he raced after Naruto. As he glanced over the village, he realized two things: it was most certainly not the same Konoha they lived in and only Sasuke, who was in Kumo, possessed the Sharringan. In an instant Shikamaru figured it all out. Thankful of the darkness, Shikamaru used his shadow to grab Naruto and pull him back from the confrontation. When Naruto skidded to his side, Shikamaru whacked him over the head.
"Only Sakura is allowed to do that!" He protested.
"You deserve it! That seal brought us back in time to the night when you were born!"
Naruto's eyes widened.
Shikamaru cursed as he realized exactly what Naruto was about to do and how there was absolutely no way he could stop it.
"That means I can save To-chan!" Naruto vanished in a flash of light, reappearing a minute later with a second man.
"Naruto, you baka! What are you thinking? That's the Yondaime!"
Naruto scratched the back of his head nervously. "Don't let him get hurt, will you?"
Muttering with annoyance, Shikamaru did as Naruto told him, holding the man with his shadows so he could not use his Hiraishin to escape. Thankfully, no one could see them from their perch on the roof of the Hokage tower.
"Who are you and what are you doing?" The Yondaime demanded while Naruto raced up to the Kyuubi and both vanished in a flash of orange light.
"I apologize for inconveniencing you, Yondaime-sama. I'm Nara Shikamaru. The blond idiot is your son Uzumaki Naruto, who I'm pretty sure both of us really want to murder right now. That idiot decided to mess with some Fūinjutsu and sent us back in time. Now, he's decided to reseal the Kyuubi inside of himself."
"You're insane."
"No, your son is.
"Release me."
"Sorry, there's this little by-law that says the most recent Hokage's commands supersede commands of previous Hokages so I have to obey Naruto first."
"What?" The Yondaime deadpanned.
"Naruto is the Nanadaime Hokage."
The Yondaime gritted his teeth and dislodged Shikamaru's control over the jutsu.
"Yondaime-sama!" Shikamaru cried out as the man turned to race towards the silhouette of the Kyuubi outside of the village. Without hesitation, Shikamaru raced after him. The Kyuubi vanished as they approached. Skidding to a halt, Shikamaru stared as the Yondaime crouched beside Naruto, pressing the tip of a kunai against the base of his skull. Naruto knelt, his forehead pressed against the ground with the Kyuubi's chakra coating his skin as he struggled for control.
An agonizing minute later, in which Shikamaru subtly paralyzed the Kage with his shadow, the Kyuubi's chakra faded into Naruto's skin.
Naruto slumped to the side, exhausted. "Don't touch him," Shikamaru threatened.
"Release me," the Yondaime ordered, leaving no room for argument. Shikamaru retracted his jutsu and the Yondaime knelt beside Naruto, rolling him onto his back and examining the seal burned through his shirt. An ANBU landed beside Minato and two others twisted Shikamaru's arms behind his back.
"Take them to T&I," Minato ordered. "Make sure the blond stays unconscious until I have a chance to examine that seal."
"I'll answer your questions without coercion," Shikamaru stated as the Yondaime ushered Inoichi and Ibiki into his cell.
"We'll see about that," Minato answered.
"What is your name?" Inoichi began.
"Nara Shikamaru."
"What is your rank?"
"Jōnin."
"What is your registration number?"
"0-1-2-6-1-1."
"What is your position?"
"Hokage's assistant."
"When were you born?"
"Sixteen days ago."
"How old are you?"
"Thirty-two."
"How is that possible?"
"Naruto."
"What does that mean?"
"Naruto did something stupid and impossible, a usual."
"How did you get here?"
"I live in Konoha."
"Why are you here?"
"Naruto did something stupid."
"What do you know about the Kyuubi attack."
Shikamaru hesitated. "That is a very, very long story, you might want to take a seat."
"Are you responsible?"
"No."
"Do you know who is responsible?"
"Yes."
"Who is responsible for the Kyuubi's attack?"
"Ultimately, Uchiha Madara is responsible."
Dead silence answered Shikamaru.
"He's dead," Minato snapped.
"At this point in time, his death was never confirmed, check the records if you don't believe me."
The three men watched Shikamaru carefully for a long time, analyzing his every move. In a demonstration of his character, the Nara watched them back, his face neutral and not the slightest bit uncomfortable. Instead of pressing for details as Shikamaru expected, Inoichi continued with the interrogation by laying down two seals.
"Identify these."
The cuffs around Shikamaru's wrists rattled as he pointed to one of the seals. "This is the remnants of the Hakke no Fūin Shiki, specifically the one placed on Naruto at his birth. During one of his fights, it's too troublesome to remember which, he unlocked the seal to voluntarily provide the Kyuubi full freedom to assist in the fight, they were friends as far as I could tell, but I've only spoken with the Kyuubi a handful of times, I don't recommend it. Naruto can show you the full version, he's the seal master. The other one, I vaguely recognize as similar to a seal he showed me a few years ago to be used should another tailed beast need to be sealed. Ask Naruto if you want specifics, no one can decipher his seals."
"This is one of my seals," Minato corrected. "It took me months to develop and it is still unfinished. How did you and this Naruto gain access to it and improve it?"
"I am from almost exactly thirty-two years in the future, Yondaime-sama. In my timeline, you died alongside Uzumaki Kushina sealing the Kyuubi into your son with the power of the Shinigami."
Inoichi shot Minato a reproachful look as the man's eyes narrowed dangerously.
"From your expression, you were planning to do just that again before Naruto and I landed in this timeline."
Ibiki looked on with immense respect for the Yondaime.
"Ever since Naruto was in the Academy, he's had a very long leash and by the time he was twelve, he successfully stole the Scroll of Seals and learned the Kage Bunshin before he was caught. I wouldn't be surprised if Naruto has had possession of your seals ever since he learned you were his father. Troublesome, he's technically older than you."
The room fell silent, unsure of how to respond.
Perfectly attuned to Naruto's chakra signature, Shikamaru smirked slightly. "If that is all, you might want to check on Naruto. He should be waking up any second now and freaking out when he senses the chakra of quite a number of people he knows to be dead."
A minor explosion vibrated the room.
"Too late. Yondaime-sama, you might want to handle this personally. Naruto is extremely powerful and if he realizes this could be a Genjutsu and tries to destroy it, there might not be much left standing of this building. I correctly assume you haven't put Naruto-proof seals on this building."
"SASUKE!" Naruto bellowed angrily. "KAI!"
In the distraction, Shikamaru immobilized the three other occupants in the room and unlocked his handcuffs, racing out to bring his Hokage under control. "Naruto! You BAKA! This isn't a Genjutsu!" He shouted back, dodging a falling beam. "Your thrice-damned seal brought us into the past!" Shikamaru rounded the corner to find Naruto scratching the back of his head, embarrassed.
"Sorry about that," he laughed, eyeing the ANBU lined up around him. Shikamaru whacked him over the head. "Ow!" The blond protested as Minato and Inoichi arrived on the scene.
"You damn well deserve it! How many times has everyone told you to think before you act!"
"But if it was a Genjutsu—"
"If you had taken a half-second to think, you would have realized what happened a few hours ago!"
"So?"
Shikamaru opened his mouth to retort, but stopped when Naruto flinched and the Kyuubi's chakra began to seep out of him.
"Damned fox doesn't like me very much."
Shikamaru whacked him again for good measure. "Troublesome," the Nara muttered and stalked away. "He's your problem now," Shikamaru told the Yondaime before leaping through a collapsing portion of the roof and Shunshining to his, as of yet, only undisturbed hiding place in the village: the roof of the Nara compound. Confident in the fact that they wouldn't hurt Naruto because if the Kyuubi inside of him, Shikamaru ignored Naruto's yowl of surprise when he finally recognized the Yondaime. The blond idiot could handle that, he wasn't elected Hokage for nothing. Besides, the clouds were making extremely interesting shapes that day.
Author's note: I'm not going to write the rest of the story, there are plenty of time travel fics out there is you want to know what Naruto would do. This idea just kept niggling at me.
Rest of the story: Shikamaru's already exhausted his proactiveness for the next decade. Naruto has the power, plus some, to defeat all of the antagonists from canon and his therapy jutsu will bring Obito back and help all the Jinchuurikis since nobody can really control Naruto. Everything's fixed, everyone's happy, Naruto's not thrilled about leaving his old friends behind but life goes on, the end.