ok i have quite a few and warning some are a bit unsavory. in no particular order
- monster/teratophilia au - i am a huge monsterfucker so im always willing to read fics that involve one of the characters being a monster/inhuman and a lot of my bookmarks involve this
- enemies to friends to lovers, reading about the relationship changing from visceral hate to cozy companionship to passionate love is always something i'm sat for
- tropes that involve religion in some way. a lot of my favorite fics involve religious guilt, corruption, divine worship, god/priest, etc. it's interesting because i've never been religious but love the exploration of this in fics
- omega/omega - it's really hard to find fics that write omega/omega in a way that i enjoy but when i do...hoo boy
stockholm syndrome - dont ask
size difference - duh
historical au - i love reading fics that take place in different points in time from the past, whether it's ancient times or just like the 80s. i always love reading the author's take about the relationship dynamics in a particular time period.