AceShowbiz -

Jonas Brothers have been very open about their commitment to stay virgin until they get married, but British singer Adele doubts the boys will resist the temptation to have sex as they are always surrounded by many female fans. "Millions of girls fancy them! If the Jonas Brothers are virgins - then I'm a man," she tells Glamour magazine.

Though admitting she is one of Kevin Jonas, Nick Jonas, and Joe Jonas' fans, Adele believes they will sooner or later break their celibacy vows. Neither of the singer brothers has offered defense on Adele's statement just yet.

Back in February this year, Nick, Joe, and Kevin told the March issue of Details magazine that they have all vowed not to have sex before marriage. Joe even publicly said he and his brothers wear purity rings as "promises" to themselves and to "God" that they will "stay pure (until) marriage."

On September 7, during their attendance at the MTV Video Music Awards, Jonas Brothers were mocked by Russell Brand, who was on hand to serve as the event's host. The actor-comedian poked fun at the threesome for more than half of the show, suggesting they shouldn't keep their virginity for marriage, but rather took advantage of their youth and celebrity status.

Despite Russell's mock, Nick, Joe, and Kevin remained positive, saying they "had a good time" during the entire festivity as they "had a lot of friends there and everybody's so nice."