But if it doesn't have a plot, ok, yeah, I'm numb to it. I've probably read something just like it before,

And that's just it, isn't it? It's hard to write sex that's never been done before (unless one brings in the squid, and that's just a maybe), so without the plot, I feel like I'm reading the equivalent of summer reruns. Especially fics that seem to think they have to describe every movement and angle.