The experience of orgasm itself is always nonsexual. Even though you have achieved it through sex, it itself has no sexuality in it.
You can reach to orgasm through sex. It is a merger of the negative and the positive polarities -- such a deep merger that the man is no longer man, the woman is no longer woman. They are not two; there is only one energy surrounding them both. They have melted into that energy.
It may be for a moment -- that does not matter -- but the experience itself has nothing to do with sex.
The first orgasm is bound to be attained through sex. And my own understanding is that meditation has grown out of the experience of orgasm, because the original founders -- particularly Shiva who, in his Vigyan Bhairva Tantra, has written, just like a scientific formula, about one hundred and twelve meditations; each meditation just in one line or two lines.... The man is tremendously aphoristic. Those one hundred and twelve sutras are just like seeds. He has condensed everything about the method in them.