Updated

The man who turned the swinging single lifestyle into a multimillion dollar corporation and global brand is, well, swinging again.

Playboy founder Hugh Hefner and his 25-year-old fiancee, Crystal Harris, have called off their wedding just days before they were set to marry.

"The wedding is off. Crystal has had a change of heart," Hefner tweeted.

Hefner, 85, and the former Playmate were set to walk down the aisle Saturday at the magazine mogul's mansion, but sources told the website the two canceled the plans following a heated disagreement.

Harris' music manager Michael Blakey told E! News that the breakup was "very sad" but "amicable."

"There are two mistakes one can make along the road to truth ... not going all the way, and not starting," Harris tweeted to her fans early Tuesday, the same day she launched her music career with the release of her single "Club Queen."

Just last week Hefner tweeted a photo of their wedding invitation.

The surprise news also came out the same day comedy site Funnyordie.com launched a spoof video where Harris talks about a new iPhone app that bridges the gap between 20-something gals and their 80-something boyfriends. (See below.)

Yikes.

Hefner had proposed to the buxom blonde on Christmas Eve with a sizable diamond sparkler.

The proposal came only months after Hefner finalized his divorce from second wife, Kimberley Conrad, despite living apart since the late 1990s. He has two sons with Conrad.

His first marriage, to Mildred Williams, ended in 1959, six years after he founded Playboy magazine. Hefner also has two children with Williams.