It doesn’t have to be a detective series or crime, though that would be fine. I really like that you’re invested in the arc of the characters, not just who did it. Not just because they might get together but where they’re going individually. I don’t find many crime series really like that, though I’m happy to be wrong! It’s reasonably complex with a lot of characters but still very readable, as I struggle with getting into books these days. Any suggestions?