"These "pleasure marriages" can last for years, months, several days, one night, or a few hours. Popular in places like Iran but also quietly practiced in America, Mut'ah is a handy option for unmarried Shiite Muslims who want to have sex without settling down for life. "There can be no sex outside of marriage," says the 29-year-old Selman, a champion weightlifter who, over the past 10 years, has been temporarily married 25 times."