Imagine, if you will, a person (of the variety to which you are normally sexually attracted) with no head.
Now imagine such a person (with their head, but) with no arms or legs.
Which is more attractive? 
(Assume in each case that there is nothing traumatic about the loss, just that they happen to be formed like that. Person with no head can think and move around and so on, but not speak, person with no limbs probably travels on some sort of floating saucer, like the Mekon.)
Or indeed, suggest other body parts that your ideal partner could do without while still appealling to your twisted sense of what's hot.
