Rona from Secret Confessions Of A Smart Girl has a little to say about being fucked from behind:

There’s something delightfully objectifying about being taken from behind. It’s not about romance, eye-contact, and connection. It’s about visceral use and physical need. It’s depersonalizing – you can’t see the person fucking you – and there is a sense of almost animalistic invitation to presenting yourself with your knees spread and your ass in the air waiting to be fucked. You know that what they’re looking at is your ass or your cunt, and all you can think about is how it will feel when they open you up and push their way in.