Not really anything to do with s/8915532/1/Clandestine but these things easily could happen in the same universe.
Introduction
He is clumsy with his emotions, a life without proper social interaction will do that to a person.
She never seems to mind, but he still feels like an alien most of the time. He never has stories like she does, about her day or co-workers.
But it hits him, finally, as he shakes some Irishman's hand. A mob doctor she knows. It's the first introduction he's experienced from her, and he's just here to stitch a wound she can't. Yet he's known her five years.
It makes him feel less alone.
She's as lonely and isolated as he is.