Just be clear what you expect from this. Be honest, and state that you don't want a serious relationship and make this clear BEFORE you have sex.
It always astounds me that men go out of their way to romanticize an encounter and seduce a woman as if they have romantic feelings when it's only about sex; why donlt they just try being honest? They might find that some women are only interested in sex, too. But perhaps some men enjoy manipulating and lying to get what they want...that way if they set up false expectations they can enjoy the hurt they cause others.
That's not to say women don't engage in this behavior too, but it's much more prevalent in men.