Rule Archer from Rule by Jay Crownover

Including but not limited to:

Gemma from A Great And Terrible Beauty by Libba Bray, and Montmorency/Scarper from Montmorency by Eleanor Updale

Ohohoho.

My crushes are all from the Silmarillion.

And it's a pretty long list:

Mairon/Sauron/Annatar (They're all the same person) Melkor Maedhros Celegorm Curufin Fingon Maeglin Glorfindel (Yes Glorfy from LOTR is in the Silm, but this is a past version of him)