The elegant Lady Footly
"The bedding is a Westerosi wedding tradition, practiced throughout the entire continent. It's intended to provide evidence that the bride and bridegroom have consummated their marriage.
The bedding is commonly held after the wedding feast is over. Male guests carry the bride while female guests carry the bridegroom to the bedchamber, removing items of clothing along the way and making ribald jokes. Although a popular tradition, it is optional, and can be dispensed with."