An "Obedient Wife Club" known in Malaysia for its controversial views has published a book urging men in polygamous Muslim marriages to have group sex with their wives, a report said.The club, formed earlier this year, has made headlines with its radical suggestions on sex and marriage in conservative, Muslim-majority Malaysia.They include earlier calling on women to be "whores in bed" to prevent their men from straying and pursuing divorce.In a 115-page book titled "Islamic Sex, Fighting Jews to Return Islamic Sex to the World," the group calls on Muslim husbands to have sex with all their wives simultaneously, The Star daily reported.One chapter, "How Sex Becomes Worship," contains unusually explicit sexual descriptions for a Malaysian publication, such as a tutorial on breast-fondling.AFP was unable to immediately obtain a copy of the reported book, published by Global Ikhwan, the Malaysian Islamic group that formed the wives' club.Global Ikhwan first shot to prominence in 2009 when it formed the equally controversial "Polygamy Club".Global Ikhwan member Maznah Taufik told AFP the book was exclusively for wives' club members and declined to comment further.The Star said Jamil Khir Baharom, Malaysia's minister in charge of Islamic affairs, has promised to investigate the book's contents.Malaysia bans books deemed to be pornographic or insulting to Islam.The "Obedient Wife Club" said at its June launch that it had 800 members in Malaysia and another 200 overseas.Polygamy is legal for Muslims, who make up more than 60 percent of Malaysia's population. Men are allowed to take up to four wives.A 2010 study by a Muslim activist group found that men in polygamous relationships struggled to meet the needs of all their wives and children, and that the result was often unhappy and cash-strapped families.Maria Chin Abdullah, executive director of women's advocacy group Empower, called the book a "very backward, narrow way of presenting women's role"."It's really an affront to the women's rights movement," she said. "We have come forward so far to say women are not just sex objects."