oooo tricky question!! i love found family, soulmates, codependency, complicated and well thought out magic systems (if that counts as a trope...) (...magic that has a price is also very fun). fake relationships is also pretty fun if done right (though i prefer it if they go straight to fake marriage/engagement bc it's so funny)

in more... uh, explicit stuff, i like it when it's separate from the plot tbh.... or if there /is/ plot, it's well thought out and engaging (and the pwp isn't like. detracting from it)

....aw man that isn't. a trope... uhhh. i like aftercare, overstim, 'there was only one bed' (or only one room left), bodyswap/telepathy hhhhh