Bellerophon — world-building for sexual tension
I don’t know about you, but I can enjoy good erotica no matter what the setting. Sci-fi adventure romp with aliens, contemporary shagfest in the back of the pub, two cowboys going bareback horseback… Actually, that last one could be uncomfortable if they fall off.
My point is I don’t need a fully developed background to appreciate a good sex scene.
But it helps.