In this 14-minute video Gene Hart discusses the link between sex without the goal of orgasm and heightened spiritual consciousness. If we would use sex for our joint reunion with the divine we must ultimately prioritise that union above the romance and hot sex we are wired to seek from each other.
However, a good starting point is to learn to stabilise our unions and make them harmonious, affectionate and caring. That’s why SynergyExplorers.org devotes itself to this practice.
Don’t fret about the kundalini, by the way. Let the exchange of yin and yang do its work without try to force anything.