The prison's new turnkey has a son named John Chivery, who is basically an emo boy: thin, pale, emotional, and constantly fantasizing about what his tombstone will say.
This John Chivery has a huge crush on Little Dorrit.
His parents are into the two of them getting married, thinking that he will bring money and she will bring social status to the marriage. This is funny, because her social status is high only for the delusionals inside the prison.
John spends a lot of time trying to butter up the Dorrit family.
Tip and Fanny put on a lot of airs and generally treat him as one step above a servant.
Mr. Dorrit, on the other hand, is happy to accept his constant gifts of cigars and pretends like he doesn't know what they're for.
One day John brings by some cigars and asks about Amy. (Amy who? That's Little Dorrit's real name, remember?)
Dorrit tells him casually that Amy is out for a walk on the Iron Bridge.
John takes off, with Dorrit still pretending like he doesn't know what's going on.
John finds Little Dorrit staring into the water on the bridge. He walks up to her and starts to propose.
Little Dorrit immediately freaks out, tries to run away, and generally seems to really really not want to deal with his declarations of love.
He lets slip that it was actually her father that hinted for him to come here.
Little Dorrit is floored that dear old dad would sell her out for some cigars.
John asks her permission to start telling her all about his feelings, and she takes him literally and declines to give her permission.
She also tells him that since he is such a nice, kind guy, she hopes he'll never talk about that stuff ever again.
He promises. Then he walks home composing sad obituaries for himself dying of a broken heart. Fast forward a hundred years and he'd be writing a depressing acoustic guitar song in his bedroom.