Menage à Trois Bingo

I have been revisiting a fic that I had abandoned back in 2014. I reread it back in November and I feel like the first four chapters are actually *good*. I wrote a couple hundred more words on it in November, and another few hundred yesterday (not so sure about the "good" factor of the newest chapter). But my characters kind of ran off in a different direction than I had expected, and now I'm at a loss as to what happens next. Not that I ever had any real plan, but even the sketchy notes I had are now somewhat obsolete.

It's a weird niche crossover. Is anyone out there into both HP and Amber that would like to brainstorm with me?

Here's the fic: https://archiveofourown.org/works/746084