Nina and Ahmad have lived happily together in their small one-bedroom apartment for years. They share the cost of groceries; they split the rent.
But in Iran, where Islamic teachings are woven into all aspects of life, theirs is a delicate — and illegal — arrangement: They are not married.
The pair is among a growing number of young couples in Iran who are living together without exchanging vows, a trend that the government says undermines the country's religious values.
Last year, the chief of staff to the supreme leader, Ayatollah Ali Khamenei, called cohabitation "shameful."
"The Islamic ruler should strongly fight this kind of...