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Fog exploded on the battlefield, engulfing Izuna. He dodged the kunai Tobirama had thrown his way and smirked and just at this moment he felt his rival litterally materialize right in front of him (what THE fUCK ?!!!) and the fog dissipated and Tobirama was here, terrible, red eyes spitting lightning, sword ready to skewer Izuna. The young Uchiha knew he wouldn't have time to dodge, that...
And then, Tobirama's blade stopped litteral millimeters from Izuna's side, the Senju frozen. They both blinked owlishly, and Izuna briefly thought about attacking, but then he recognized the expression on his rival's face and, ah... The disgusted scowl could only mean one thing.
And indeed...
"Moon sickness strikes again," Tobirama groaned, lowering his sword and taking a step away, obviously squeezing his legs together and contracting his abdominals under his armor,"do you happen to have supplies ?"
"Yep, yep," Izuna said, searching his pockets before throwing a tightly wrapped little box to Tobirama, who caught it before it hit in the face.
"Thanks man," the Senju grumbled,"appreciated. I'll repay you later."
"You'd better !" Izuna bellowed at Tobirama, who was retreated behind the trees.
Of course, it was at this exact moment that Madara (mother-hen extraordinaire) chose to land next to him, followed by his faithful rival (who didn't fight other Uchiha unless somebody Izuna could name, no he wasn't jealous, shut up Aniki !). Madara who was ready to throw a fit. Izuna, ever the little shit, grinned.
"Nice day, isn't it, Aniki ?" he drawled.
************
Tobirama was three years old when he understood that despite not having the right parts, he was a boy. Fortunately for him, his father was very understanding (Butsuma didn't care what gender his children were as long as they were able to punch an Uchiha in the face. Tobirama was very gifted when it came to punching Uchiha in the face), and had gotten him boy's clothes and had taught him how to throw kunai and shuriken and overall how to kick ass.
Concerning Hashirama, Tobirama was pretty sure that his brother had totally forgotten about his birth gender (he was right). The other Senju didn't care, as long as he was able to protect them. He was able to protect them, a little to much sometimes, the Elders had once again told him to calm the fuck down with his necromancy attempts, this was the third zombie uprising in as many weeks.
Just like Tobirama, Izuna was three years old when he had understood that despite not having the right parts, he was a boy. Tajima had told him that boy or girl, it was still his turn to do the laundry today and that he wouldn't escape the chore. Then, he had given him a little armor, a set of kunai and had taught him how to breathe fire and punch Senju in the face (Izuna liked punching Senju in the face).
And Madara, just like Hashirama, had forgotten that his brother had been born a girl.
************
"What the fuck was that ?!" Madara hissed, red in the face, waving his gunbai threateningly, and overall looking one hair short from apoplexy.
"What was what ?" Izuna asked innocently, batting his lashes.
"This fucking Demon could have killed you, but he didn't and then you gave him something and he left ! I saw it, don't try to deny it ! What was that ?!"
Izuna shrugged and rolled his eyes.
"Moon sickness," he grumbled.
Both Madara and Hashirama made a face.
"What ?" Izuna groaned, recognizing their shared "we're about to say something incredibly stupid" face. No wonder these two got along so well, they both were idiots of equal levels (very very high level, if Izuna was to be honest).
Tobirama reappeared at this moment, walking a little gingerly, and scowling. He was holding the wrapped box, that he chucked at Izuna's face, who caught him and stuck his tongue at the childish Senju, who rolled his eyes in return.
"Where did you find them ?" Tobirama asked as Izuna pocketed the box,"they're way comfortable than mine, I..."
He didn't have the time to finish his sentence, since Hashirama engulfed him in a bear hug, while crying crocodile tears.
"TOBIIIII !!!! Why didn't you tell me you were going to die ?!!!!" he howled a his hissing brother.
************
Problems came with puberty, when at thirteen, Tobirama woke up in a pool of blood and feeling disgusting. He went to his father, who tried to explain him what was happening without pronouncing the word girl or woman (this was oddly touching) once. He then went to Toka, who had shoved a little box wrapped in an innocuous fabric and taught him how to use what was inside. This was odd, but better than blodd dribbling down your thighs all day.
At fourteen, Izuna had (fortunately for him) escaped the ordeal of menstruations. However, it was this year that he found himself on a joint mission with Tobirama Senju of all people (curse the idiot who had that idea, curse them to hell and back). And since the Universe hated him, it was at this moment that Mother Nature chose to strike.
He had woken up in a pool of his own blood, had understandably screeched, waking up his rival (because yes, they had been forced to share the same tent). He had expected the Senju to laugh at him and mock him, but Tobirama had just thrown a box in his face and told him to use it. After a lot of explanations and a fucking desmonstration on how to use it (he had been unable to look at Tobirama in the eye for days, it had been hell), Izuna had gone on with his life like nothing had happened (nothing had happened, it was only a fever dream, this was his version, and he was sticking to it !).
(Tobirama Senju had NOT shown him how to use a fucking tampon ! No, nope, noppity nope !)
************
"What the fuck are you talking about, Anija ?!" Tobirama protested, swiftly escaping the bone-crushing hug.
"Bu... but Izuna said you had a sickness ! Why didn't you tell me you were sick Tobi ?!"
"A sick... oh, moon sickness ?"
"Yes, that !!!" Hashirama screeched,"MY BABY BROTHER IS GOING TO DIE !!!"
Tobirama, wide-eyed, looked at Izuna, who shrugged and made the universal sign for "your brother is nuts".
************
They had met on other missions, sometimes on the same side, sometimes on opposite sides. However, they had quickly reached an aggreement concerning what Tobirama had dubbed "moon sickness" in a fit of drunken poetry when they were both sixteen. There would share the supplies in their possession if it ever happened to them while together on a mission (no matter the side they were on at the moment) because this was annoying and disgusting and they didn't wish it on their worst enemy.
(This also how they became friends, even if they both would rather die under torture than admit it.)
************
Izuna rolled his eyes, tired of the Senju Head's dramatics.
"He's not going to die, you..." he started, but was interrupted by none other than Tobirama.
"Actually, I am going to die," he said in an even voice, face blank. Hashirama started wailling more loudly. Izuna made a face at his rival, who raised his eyebrows and winked at him. Izuna choked on a breath and almost started laughing when he understood what his rival had in mind.
(There was a point on which they were exactly the same, it was that they loved getting a good laugh at their brothers' expense.)
"I suffer horribly," Tobirama said, voice even, and Izuna wondered how he was able to say such bullshit without laughing. He himself would be unable to reach that level of pokerface.
"Izuna has it too," Tobirama added with the tiniest hint of a smirk and it took all of Izuna's willpower not to spill to beans by howling with laughter there and then. Instead, he composed himself a contrite face when Madara turned to him, looking horrified.
"Why did you not tell me ?!" his brother screeched.
"I didn't want to sadden you, Aniki," Izuna said, adding just enough remorse in his voice to make it work.
"What can I do ?!"
"Nothing, unfortunately," Tobirama said, from where he was trying to escape his brother's octopus hug," it's incurable."
Madara's face was ashen.
"Then, what do you want ?" he asked.
Izuna glanced at Tobirama, who winked, and then he smiled wobblily at his brother, before throwing himself in his arms.
"Why not a place where we could spend the rest of our days in peace ?" he said. He forced tears to gather at the corners of his eyes.
Madara and Hashirama looked at each others.
"Yes, yes we're going to do that !" they cried.
************
Watching Madara and Hashirama bulldoze their way over the Elders had to be the funniest thing Izuna had ever witnessed. Of course, after some time, most kunoichi (and some shinobi) of both clans had understood what was going on and had joined the party by going to their Clan Head and pretending they also suffered from moon sickness.
Peace was had, a village was built, and both clans got surprisingly along, busy that they were laughing at their respective Clan Heads' stupidity. And then the Hatake were invited to join the village.
************
"Tell me," Hashirama said to Sara Hatake, matriarch of the Hatake Clan and their aunt on their mother's side,"do anybody in your clan suffer from moon sickness ?"
Sara Hatake blinked at his nephew, flanked by the Uchiha Patriach, then looked at his other nephew, who was sprawled on a pile of cushions with the Uchiha Heir, munching loudly on dango. There was a mischievious glint in his red eyes.
"Moon sickness," she said flatly,"do you mean menstruations ?"
Hashirama blinked, so did Madara. The gears in their brains obviously started turning as steam got out of their ears. Then, they whipped on their heels to face their lounging brothers, looking absolutely scandalized.
"Menstruations ?!!!" they squawked indignantly.
"Hum hum," Tobirama said, still munching on his dango.
"You told us you were going to die !"
"True. But we never told you we were going to die from moon sickness."
Izuna, sprawled on Tobirama as if the bigger Senju was a mattress, smirked, and Tobirama's shark smile split his face in half. Their brothers' faces became blue.
"YOU'RE GROUNDED !!!!"