The one who celebrated his cupper wedding with the kidney of someone else.

Daycare Hospital, Nephrology, Sixth year.
I grab the following file of the "Annual checks" pile and open it.

I like to picture the transplant physicians as a form of National Matrimonial Agency.
"Nothing will ever prevent us from finding you the perfect HLA-match, so let's sign up now !'

We have to acknowledge it, organ transplantation is a complex process requiring a huge amount of concessions.

The recipient, in need by definition, is accepting the graft by doing some sacrifices.
He has to rethink the notion of "self" and the idea of autonomy. Which, i bet, does not come that easily. He also have to make a clean sweep of his past, muting his immune system oftenly using heavy treatments.
And yet, even if they are sometimes grumpy, the recipients rarely refuse the idea of this planned matrimony. Their destinies rely on it. They eventually are the ones soliciting the services of the Transplanting Agency.
So, our recipient is in waiting (sometimes for quite a long time). And suddendly, one day, the Agency calls because it has a match and has set up a meeting.

On the other side, the story of the sweet graft is quite different.
Rarely spontaneously offered, it is oftenly torn from its homeland while things are seriously going crazy. It is seperated from its birth-organism, arteries cut, and bend to another body. Maried by force to a great machinery more or less functional requiring its urgent and constant services.
So, expectations towards the newcomer are somewhat huge. 

Since Romeo and Juliet have finally met, the transplant physicians pamper them.
They do all they can in order to put on soft mood music (peaceful immune environment), make sure that everyone feels comfortable (clinically and paraclinically) and then hide in a corner (behind some computer) and do what every matrimonial agent would do : wait.

Sometimes, none of the main characters can suffer the other one. The first one is attacking the second evoking some old love story (aka transplantation) that had gone mad. The weapons are an immune battery able to recognise every graft that more or less looks like the previous one. And on the other side, the second is panicking because it has suddenly understood that he wasn't home and is so terrified that it tries to burn everything down.

Sometimes, it goes softly. The protagonists can understand each other. They cohabitate by doing some concessions and go every year to the Agency for their "Annual Check up". Then, they do the  together. This kind of relationship usually lasts for a decade. Ten or fifteen years of good services, then the two of them get tired and the story ends.

And sometimes, rarely but sufficiently anough for a chatty student to meet them, it is love at first sight. The recipient end up living with the graft longer than his own previous organs and the graft feels so comfortable that we can't tell it apart from the host.

The smiling man and the zen kidney i met this day were of these misfortune lovers. When i opened up the file that day, i saw the pre-filled column saying : "Annual Check up of the thirty-two years".

I looked up to the transplant physician still hiding behind his desktop, his finger on the mood music prescription, and raised a thumb. Well done.