Prussia finds himself trying to forget Austria's past more than he'd like to admit.
It isn't something he actually brings up with the man though. No, he keeps it to himself as he's lying in bed at night, kept up by lingering thoughts. Austria sleeps beside him, facing away and curled into himself. And Prussia thinks.
He thinks about Hungary and Spain and France and Turkey and the Holy Roman Empire and his brother, his thoughts even drift towards Serbia, only to be gathered up and set in another direction, and anyone who had (he assumed) laid a hand on Austria in the past. Even Russia, the bastard, had stolen away his attention if only for a moment. And he can't help but feel jealous.
He thinks about Hungary and Spain the most, though. About how they were actually married to his little aristocrat so long ago. And Prussia gets angry - furious, even though he knows he can't change the past - roughly waking the other up with a demanding kiss. Austria, still half-asleep, returns it more peacefully, wrapping his arms around Prussia's neck and falling back into sleep.
He calms quickly, cradling the other's head in the crook of his neck and placing small, unnoticed kisses to any spot he can reach as silent apologies.
Eventually, his train of thought wanders back in that direction and he hates it. Hates his mind taunting him with imagined images and unreal scenes. As he pulls Austria closer, Prussia forces his thought toward a better path, listing all the good things in his life as he could possibly remember.
It took a bit longer than usual but he drifted to sleep a few hours later, a cheeky smile adorning his lips.
After all, they had their chance.