Hello, everyone! This another Naruto/Fullmetal Alchemist crossover challenge, staring Sasuke Uchiha as the main character. I've read a few Naruto/FMA crossovers, and felt disappointed at that Sasuke is only in a few of them, so there needs to be more. I don't care what anyone says, but Sasuke is my favorite Naruto character! Just putting it out there. And recently, I've been reading quite bit of angsty Sasuke/fem-Naruto stories [OTP Naruto pairing by the way]. Mostly one-shots of Naruko dies and Sasuke is grieving. And this story has the exact same premise for Sasuke's backstory, sort of.

This would be a sort of dark-Sasuke fanfic. Dark? Well, I don't know how to explain since Sasuke is/becomes dark in the second half of Naruto. Just imagine the Sasuke during the Kage Summit Arc, except less...insane [at least outwardly, I suppose]. You know, the one that goes crazy after Itachi's death and finds out the real truth behind the Uchiha massacre. Yeah, that Sasuke. And also a bit of a yandere Sasuke for a deceased Naruko.

Oh, yeah, and before I forget, this isn't some story where the Naruto characters transfer into the FMA world by some jutsu or something. Naruko and Sasuke are born in the FMA universe. They are not reincarnated either. They were simply born and raised in Amestris. So, no jutsus, just pure alchemy.

Okay, the rules…

1) Like I said, this is a dark Sasuke fanfic, so make that what you will. Don't get it confused with evil. Sasuke is not a villian or villain protagonist [or deuteragonist, like in the second half of Naruto], but more of an anti-hero. Unlike Edward, who is martial pacifist [meaning Ed isn't afraid of beating people half to death, but would never go for the kill/fatal blow], Sasuke isn't afraid to manipulate and kill if necessary.

2) Like I said semi-yandere Sasuke, meaning a Sasuke who becomes possessively murderous over Naruko, who is dead. By the way, he keeps a picture of her in his pocket watch. Make that what you will. A Sasuke who goes completely murderous on anyone who insults and belittles Naruko and anything she stands for, whether intentionally or not. Just imagine Shion Sonozaki who went yandere after Satoshi Hojo's 'death'. If you don't know who those characters are, watch Higurashi because I'm not spoiling it. Be warned though, it's a psychological horror/mystery anime/manga. So make sure to be mentally prepared before watching/reading. That's all the warning you'll get from me. It's infamous for a reason.

3) The only reason Sasuke is in the military is because he made a promise to a deceased Naruko. What kind of promise? Well, that's for you to decide. But it has been something that keeps him going completely off the deep end. His only reason for living.

4) Of course, both Sasuke and Naruko are orphans. And of course, somewhere along the lines, Naruko dies that what turns Sasuke into the Sasuke he is now. Oh, and Naruko died at least a year or two before Sasuke became a State Alchemist

5) As for pairings, none… At least for Sasuke. I would say a gen fanfic [meaning, absolutely no pairings], but if you want canon pairings, like Edward/Winry, Alphonse/Mei, Roy/Riza, etc., go ahead, but none for Sasuke. Sasuke had always and would always love Naruko.

6) NO HAREMS OF ANY KIND!

Of course, I'm expecting Sasuke to gradually get better. It's called character development. Oh, and what kind of alchemy would Sasuke be using? Basically, lightning alchemy. Pretty much, chidori and all its variants, except, well, it's alchemy.

Well, that's it for challenge. Happy writing!