‘Let’s talk about sex, baby,’ sang female rap duo Salt-N-Pepa back in 1990. More than 30-years later, it can seem as if we talk about little else. Today, we are not just expected to talk frankly about all matters carnal but to be ‘sex positive’. Emma Sayle, the founder of ‘Killing Kittens’ – which organises posh orgies for bored bankers – is the latest to urge us to speak up about sex.