The game is so called because the player seems to remove anything that comes between the Queen and the King of the same suit for them to "marry." Although the King and the Queen may be of any suit, commonly it is the King and Queen of Hearts that are being "wed." For this same object, this game is also called Betrothal.
The Queen of the suit chosen (most commonly the Queen of Hearts) is placed immediately on the table while her corresponding King (in this case, the King of Hearts) will always be dealt last. The remaining fifty cards are shuffled and placed on the top of the King.
Cards are dealt one at a time to the right of the Queen. When a pair of cards with the same rank or suit are found to be separated by one or two cards, those in-between cards are discarded. Afterwards, the player can look for any resulting pairs with in-between cards to be discarded.
The game is won when Queen and the King are brought together with all other cards discarded.