The strangest thing about the start of the war is that they cease to go outside.
The flat becomes a country; its borders the doors and windows, a new state christened with each archway, the tiny bathroom an island, the kitchen a principality (Remus').
It's so sparsely populated that it allows them to be new people, for no one can say any different. One day they live in the county of Bedroom, dozy and soft, whales perhaps, drifting on waves and ignoring the spray of harsh rain as it hits the window and they twist, rolling, in and out of sleep.
Another day they might live in the kitchen as royalty, Sirius playing footman, Remus perched on a stool writing his personal decrees. The bathroom, of course, is for pirates.
They alter the laws every day; dissolve the old, install new ones. Remus' favourite is perhaps the Law of Quiet, whereby each morning lies silent as he wakes first, and can read whilst Sirius snores (quietly) into the pillow beside him. Sirius' favourite is hard to choose, but he thinks in the mornings it might be the Law of Lie-Ins, drawn up soon after his need for an alarm-clock disappeared.
Remus seldom writes the laws, but is initially easy enough to convince. By the time Sirius brings up the Law of News, Remus greets the revelation with only a small nod, a half-smile over his breakfast. They shut the borders together, so no News can sneak inside. The rustle of broadsheet paper becomes contraband. They're happy.
The flat's ecosystem rarely tips, either; all is held in balance once the borders are shut, and since Remus' consititution never changes and (to his knowledge) nor does Sirius', it's easy to keep track of. He thinks, one day, that it might be easy to be a King, if all countries were as small as this. His land has all he needs, and rarely asks for upkeep; he has his love, his food, his warmth in this place, and all else is fit to be ignored. It's a perfect existence.
But Remus, after a month, doesn't seem to think so. He breaks the Law of Lie-ins, and drags himself out of bed at five in the morning to pace raggedly in the bathroom. He breaks the Law of News, opening one of the borders to allow an Owl in, and taking the tightly wound Prophet from its illegal claws. He reads it, to Sirius' chagrin, and breaks the Law of Getting Along (newly written) by throwing it down on the kitchen table and shouting like it matters, and making Sirius shout too.
He doesn't want to war, but this is what they come to, when Remus is no longer willing to play.
Some days they're still new, though; still abiding citizens and Law-makers. Some days the news disappears. Remus conforms to the Law of Lie-ins, in a way, staying in bed though he isn't sleeping. Sirius wants to invent a new Law, perhaps a Law against Sadness, a Law against Aging, a Law against Outside, but can't think of a way to enforce it and feels his authority dwindle against the pushing that comes from all sides. He settles on a Law of Love instead, but this proves equally difficult to structure, to place within guidelines; even, sometimes, to abide by.
He needs police, an army; he needs his boundaries built up; the door swings open too easily, the windows rattle when it rains, the walls let in the cold. The influence of other places crawls over the edges of everything like a fungus and his world, this world they made together, rots.
Sometimes it's not a country at all but it's still alright when Remus slides onto the sofa beside him and takes his hand and whispers sorry against his face. Sometimes he can forget the outside which is raging against him and throw away fear and danger and death. Sometimes the Law of Love is enough, is all they need, even though he's still working it out, and it's not really a 'proper' law, yet.
The Flat Country dissolves in less than six weeks, its fabric too weak to sustain the illusion when Remus keeps leaving for places unknown and James visits to help him break the Lie-In Law, but he and Remus are still an island, sometimes.
An island of arms, still protected. Still safe.