YES EXACTLY THIS wrt Farthing. I tend to slash anyone and everyone who shows up in an English country house with each other, and having come through eg. Brideshead Revisited and Jeeves and Wooster and the like, I just expect it all to be pretty gaylicious. Then it ACTUALLY IS and I'm like -- wait, what? Oh!

I actually had that experience with Willow and Tara in s4 Buffy too. I was watching it thinking they seemed kind of... oh wait, they *are*.