legal contract between a man and a woman of their free wills
Islamic law has the concept of marriage called Nikah (نكاح). Normal marriages do not end, unless they are divorced. In addition, there is a marriage for a given time, called Nikah Mut'a. Sunni Islam does not recognize Nikah Mut'a; they say it is a legitimisation of prostitution. Despite this, some Sunni schools of law have developed similar concepts.
In Nikah, both husband and wife are asked three times for consent to intercourse with witnesses so later on no one can claim rape.