suggest a book with well-written characters and relationship dynamics to get invested in?

i love character-driven stories… in-depth characters that feel almost like real people that you learn about and get attached to as you go on, and the relationships between those characters (not necessarily romantic!)

my specifications:
– no sci-fi or fantasy
– not YA / feels like its meant for teenagers
– mainly adult characters
– if it’s romance, LGBT is preferred! either wlw or mlm, no preference over one or the other
– if nsfw, not heavy/the main focus

any suggestions for something like this? it doesn’t have to fill all of my specifications besides the No’s. thank you!!

by meenbeen9899