You and Tom met in... unexpected circumstances.
Turned out you and him were visiting the same vet, and when one time you both visited it at the same time, your dogs, both golden retrievers, decided to have a little fun, while you two were busy talking, while waiting for the appointment.
And this "fun" ended up with your dog's pregnancy.
And there wasn't much you could do in this situation, except for coming to terms with the fact that soon your dogs will have puppies. But as time went by, you both god quite excited about it, you exchanged numbers, visited eachother a few times and became friends.
But as the time went by, your dog obviously got birth eventually, and you called Tom, telling him about the four puppies your dog got birth to.
Now you waited in your living room for him to visit you, while suddenly you heard the doorbell.