It's easy for the body to be open to desiring different people because desire wells up & demands to be satisfied. It's easy to categorize corporeal desire as sexuality, but if it has no means of merging with spiritual desire, then a rupture will occur between sprit & flesh. For ultimately passion & sex aren't only expressed physically but through a true union between two spirits. When the spirit can truly love & find contentment, both the body & the other key aspects of life will fall naturally into place, working in unison, merging.