Must be approved by the empress, or someone the empress determines to be fit to do said task.
3-way marriages are allowed, with consent from all 3 parties.
Marriage is a legally binding contract to love and cherish for a period of 5 years, then it may be refreshed or dissolved appropriately according to the couple's feelings at that point.
After marriage, cheating for the sake of this law means: any insertion of male genitalia into any female orifice. (example: cheating: a man screws a prostitute without his spouse's awareness or consent. This is grounds for cheating.
Cheating is grounds for punishment determined by spouse, or parental unit/owner (usually slavery)
*note: If the spouse allows, either partner may have relations with professional prostitutes as long as said encounter does not result in illegitimate children*
“Love” is required, a a couple must have been together in a loving relationship for between 3-5 months depending on situation.
Divorce is legal as well, but only after a waiting period of one week, to make sure it's what they truly want.