It's Biden in the buff.

A forthcoming book that claims to give a behind-the-scenes look at the people the Secret Service protects reportedly airs some tantalizing details about Vice President Biden's swimming habits.

According to a New York Daily News account of the book, Secret Service agents say Biden likes to swim nude -- to the chagrin of some in his detail.

"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," journalist and author Ronald Kessler reportedly writes in "The First Family Detail," due to come out next week. "Female Secret Service agents find that offensive."

Scandalous tidbits from the book -- including about the Clintons -- have been dripping out over the past several weeks, in the lead-up to the release. According to the Daily News, Biden's skinny-dipping isn't the only thing agents complain about.

They also reportedly worry that the vice president puts too many restrictions on his detail when he's in Delaware, keeping them from interfering with his neighbors. One unnamed agent reportedly voiced security concerns about this practice.

Kessler claimed that the Biden detail is considered the second-worst job in the Secret Service, next to the Hillary Clinton detail.

Kessler used to work for The Washington Post, and later went to work for the conservative site Newsmax. He has written extensively about the Secret Service, and broke the story in 2012 about the prostitution scandal involving agents during a presidential visit to Colombia.

His books, though, have been trashed by Democrats for their sometimes-sensational elements, attributed to anonymous sources.