It is generally well known that the Shi'a are a sect which are unique in allowing for a form of marriage known as Mut'ah (temporary marriage for pleasure). The rest of the world denounces this concept as thinly veiled prostitution. There is even a famous documentary Prostitution: Behind the Veil released in 2004 that explores the reality of Mut'ah/Sighe marriages in Iran (a predominantly Shi'a country).
However, do not think that the Shi'a are alone in allowing for such an absurd idea as temporary marriage. Another equally if not greater misguided sect, the Barelwis, also permit the concept of temporary marriage. In the book Fatawa Africa of “Ala Hazrat” Ahmad Reza Khan Barelwi, the following fatwa is present:
اور اگر نکاح بے قید مدت کیا اور دل میں یہ ہے کہ اتنے دنوں کیلیۓ کرتا ہوں پھر چھوڑ دوں گا یا عقد نکاح میں ایک مدت کے بعد طلاق دینے کی شرط لگائی مثلࣰتجھ سے نکاح کیا اس شرط پر کہ اتنے دنوں بعد طلاق دیدوں گا یا پہلے باہم گفتگو ہوئی تھی کہ اتنے دنوں کے لئے نکاح کر لیں پھر نکاح مطلق بلا قید کیا تو ان سب صورتوں میں وہ نکاح صحیح ہوا
Translation: “If someone married without any restrictions on the duration of the marriage, but in his heart he intended to marry for a certain number of days and then separate, or if it was stipulated in the marriage contract that after a certain period divorce would occur, for example, 'I marry you with this condition that after a certain number of days I will divorce you', or if before the marriage it was verbally agreed that the marriage would last for only a certain fixed period...then still the marriage was done completely without any time restrictions, then in all of these scenarios the marriage is correct.”
Reference: Fatawa Africa, p. 52