Prompt: Move.
The moving in is gradual, and then not. There's a shift toward the domesticated – suddenly his bathroom has face creams in it, and the sight makes his heart beat a little harder in the morning. He forces himself to stay offhand and casual as he gives her keys to his house one day, and she forces herself to accept them with nothing more than a smile and a kiss on the cheek, and then he goes to his office and she goes to her desk and they can't wipe the smiles off their faces. She'll wait for him after she's finished at the office if he won't be long, but if he has a lot left to do, she goes back to his place and hangs out with Jack and Jessica. Before long, the two women are friends, and Jessica will leave Jack with her without a second thought. Hotch tells Jack he can have anything he wants for dinner on his birthday, and after making his requests he says, "Emily's coming, right? I want Emily to come." She still goes home every now and then, though, because she doesn't want to push him and he doesn't want to push her, and neither of them want to push Jack.
And then there's a few hellish weeks with cases almost back to back, and they only get a few nights at home and she spends them all with him. And when they finally get home with a few days off promised, Jack is waiting up for them in his pyjamas. He hugs Hotch then wraps his arms around Emily's hips while she's still hanging up her coat. She laughs and crouches down to hug him properly. Jessica nudges Hotch. "When are you going to ask her to move in?" she whispers.
And when he does, it's easy. They're lying in bed, her head on his chest and his fingers languidly toying with her hair. She's breathing slowly and deeply, and he thinks she might be asleep until she taps her fingers a little on his chest. "What's wrong?" she says sleepily.
"Nothing, sweetheart. I'm okay."
"Then what are you thinking about?" She knows there's something – it's in the tension of his muscles, the way the hand resting over hers on his chest can't quite keep still.
He's still and silent so long she wonders if she'll have to tell him nobody falls asleep that fast.
"Emily?"
"Mm?"
"Move in with me."
"Okay."
"Really?"
"Really."
She yawns and he holds her closer, kisses the top of her head. "We'll talk in the morning."
"Goodnight Aaron."
The next morning, they tell Jack that Emily's going to move in. His brow furrows. "I thought Emily already moved in."