That "ol' black magic" is a fickle force. The chemistry of romantic love can trigger the chemistry of sexual desire and the fuel of sexual desire can trigger the fuel of romance. This is why it is dangerous to copulate with someone with whom you don't wish to become involved. Although you intend to have casual sex, you might just fall in love.
Helen FisherYou don't come home from the office to spend time with another job. Hopefully you come home to someone you can have a good time with.
Helen Fisher