Listening to this on audiobook, narrated by David Pickering, I have laughed so hard so many times.
Poor Bingley is ADHD, with a big time (purely platonic) Man-Crush on Darcy.
He is an innocent, yet very sincere young man trying to find his way in the world after falling in love with Jane and being convinced she didn't love him back.
The back story timeline is canon P&P, with some jumps. We are literally in his head, hearing his every thought.

There is something a little raunchy/tongue in cheek/double entandre about the story. Only adds to the humor.