The Secret Service agent who guarded President Clinton during his sexual affair with Monica Lewinsky says the president was actually having sexual relations with numerous mistresses, including Eleanor Mondale, the daughter of former Vice President Walter Mondale. In his forthcoming tell-all book, “Crisis of Character,” Gary J. Byrne describes how he walked in on Bill Clinton and Ms. Mondale. “There before us was E! Network host Eleanor Mondale … and President Clinton in a compromising position, that is, making out on the Map Room table,” Byrne writes of the alleged Christmastime event during the middle of Clinton’s presidency, according to...