This is the way I originally envisioned the thing, as set in the actual ancient Roman Empire:
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[li]Sigrun, Mikkel, and Emil are all slaves who were captured by the Empire, Sigrun at a very young age and Emil at the start of the story when he's closer to his canon age of 19. Sigrun is a gladiator and Emil soon enters the ring as well; Mikkel is a slave who's had some training in medicine.[/li]
[li]Despite having lived in the Empire since childhood, Sigrun's Latin is pretty much limited to "Ave, Imperator, morituri te salutant." She immediately latches onto Emil by virtue of him being one of the few people she can talk to. (Mikkel is perfectly fluent in Latin, thank you very much.)[/li]
[li]In canon, I'm convinced that Sigrun has severe untreated ADHD. In this AU, though, it's entirely possible that she's suffered from childhood lead poisoning from lead-lined Roman aqueducts, which can also cause learning disabilities. Mikkel, who knew better, avoided drinking any water that came from those pipes, and after he met Sigrun saw to it that she and Emil didn't drink the stuff either, but in her case the damage had already been done.[/li]
[li]There's not really a place for any of the Finns in this story, sorry. Reynir is around, though: he's the son of a wealthy Roman family who quickly picks Emil as a favorite once he enters the ring.[/li]
[li]...this story wants to be Emil/Reynir, because my muse hates me.[/li]
[li]Speaking of Emil, with Sigrun teaching him he eventually gets to the point where he can step into the ring and not die. When it finally hits him that this is supposed to involve actual killing, though, it does not go over well. First time ended with Sigrun pinning him after she won a round against him (facedown in the dirt, to keep him from dishonoring himself by screaming like a baby), and though he was too grateful to feel anything but relief after the crowd called for mercy, he later couldn't stop wondering whether she actually would have killed him if they'd instead given her the thumbs-up. The first time Emil has to make a kill or forfeit his own life, he was severely traumatized and refused to talk to Sigrun for days.[/li]
[li]Meanwhile, Sigrun (with Mikkel's help) has been fomenting a gladiator rebellion for some time now so she can be free to fight on her own terms, but Emil somehow provides the catalyst that pushes her into actually doing it. They pull it off and successfully escape into the wilderness while Rome is sacked, but somehow end up getting stuck with this utterly clueless civilian in tow...[/li]
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