She knows who it is. Knows that knock exactly and grins when she hears it. The food on the stove gets covered and Charlie hurries to the door. Yes, hurries. She doesn't usually hurry to open the door, just takes her time within whatever's considered polite.

But this is Ed.

She's grinning when she answers. He's already been invited in once. She doesn't have to do it again, does she?

"Hey," Still, a subtle tilt of her head to the interior of her apartment and she steps aside to let him in. "I'm happy you're here. There's a friend of mine I want you to meet."

Because that's what people do, right? Introduce the people they're in a relationship with to the people they're friends with?