No, I would say sex is more of a demand. poor children starving is a need, lose some weight is a need. Sex is for pleasure, and pleasure is not a need. Though there are those who demand sex to keep them satisfied in the lust, there perversions and immorality. And no offence! Lust is not a need, perversions is not a need. Men and women don't need sex, but sex needs men and women. and that's the closest to need.
Sex is a controller of men and women. So the question is? do you need to be controlled by sex? No, would be the answer, however, sex does controls us men and women. So then people are reliant on sex, and possibly give the impression that it's a need.
The need to repent from sexual perversions, sexual immorality, lust, and any way sex is used in the wrong way, that will be more of a need.