Novelish

No, really. He was in love with Grindelwald - a revelation that reportedly led to several minutes of cheering from the audience.

More information in the link, but J.K. Rowling finished by saying: “I had to give you something to talk about for the next ten years… just imagine the fan fiction now.”

And, honestly, my first thought was of the childlike excitement this would give the fan fiction community. There’s already a discussion about it on FictionAlley.