Psychopaths in real stories often manipulate others by feigning emotions. For example, they might pretend to be in love or be a really good friend. They know how to mirror the emotions and behaviors of those around them. So, if they want to get close to someone, they'll act just like that person wants them to act.
People fall in love with fiction because it offers an escape from reality. It allows them to enter different worlds, experience various emotions, and meet interesting characters. For example, in a fantasy novel, one can explore magical realms and go on epic adventures.