He was going to meet her at the airport, give her a big hug to reassure her that the mutual attraction was as real in real life as it was on the internet, and then ask her if she still wanted to give up her individuality and become his pet for a week... But then he changed his mind. About asking.
A drink with some friends from work, a walk home alone in the cold night. A sudden need for a toilet. She did not want to stick her ass out in the cold weather. She was just around the corner from his apartment and she had a key to his place for emergencies... She was sure she could sneak in and use the bathroom without him waking up. She was sure of it. After all, she could be very quiet. But soon she found out that she could also be very, very loud.
The girl has arrived, and is undressed, blindfolded, and tied up on the bed as an offering... He and his wife makes sure she gets a warm and wet welcome.