These 2 images sum up what I love about this particular subject thread.
1) I love the way they've been bound facing each other - legs apart and the chains around their waists forcing his cock against her cunt! Looks like he's got a few whip marks on his ass - you can imagine their torturers whipping their asses at the same time - and he has to hear his wife groaning with the pain as her ass is punished!
2) This evokes one of my favourite scenarios - an innocent couple subjected to to a terrible ordeal. He has to stand there naked and watch as his wife is stripped to her underwear - as they remove her bra he knows it's only a matter of time before she's stripped naked. Imagine if he found the whole thing a massive turn-on and developed a massive erection before shooting his load as he watches his beloved wife being violated!