"Agents say that, whether at the vice president's residence or at his home in Delaware, Biden has a habit of swimming in his pool nude. Female Secret Service agents find the behavior offensive," Kessler writes.
"Biden likes to be revered as everyday Joe, and that's his thing" says one unnamed agent in the book. "But the reality is no agents want to go on his detail because Biden makes agents' lives so tough."
Kessler writes that Biden's "lack of consideration" means he is considered the second-worst assignment in the Secret Service, after Hillary Clinton.
The book also claims Biden does not take proper security precautions in his home state of Delaware. Not wanting to disturb his neighbors, Kessler writes that Biden travels with a more limited motorcade, leaving his military aide and doctor to follow a mile behind his limousine.
"What’s going to happen is either you're going to have a dead vice president in Delaware or you're going to have agents killed in Delaware because Secret Service management refused to stand up to (Biden)," says one anonymous Secret Service agent.
Kessler has been criticized in the past for inaccuracies in his works and for endangering the safety of those he writes about. In a 2009 review of his book "In The President's Secret Service," James Bamford wrote in The Washington Post "what is truly dangerous is the kind of National Enquirer-style gossip in Kessler's book."
A spokesperson for Biden declined to comment on the book.
Whether there is any truth or not to Kessler's book, Biden certainly appears happy to play up the image of a normal guy. On Thursday, he posted this picture of a himself as a younger man, purportedly to encourage his followers to sign up for health care coverage: