For the past year, I've been in a friends-with-benefits relationship with Aian. Thanks to our incredible physical chemistry, she's transformed into a horny, slutty girl who comes running whenever I call, eager to have sex with me. To keep things strictly casual, I always make her read the five rules of our no-strings-attached agreement before we sleep together. Today, feeling a bit bored, I gave Aian a call—and she responded immediately, clearly desperate to get fucked.