Justin Hemmes' girlfriend Madeleine Holtznagel almost has ...

Justin Hemmes' girlfriend Madeleine Holtznagel almost has ...
Justin Hemmes' girlfriend Madeleine Holtznagel almost has wardrobe malfunction ...

She's the stunning Aussie model dating pub baron Justin Hemmes. 

And on Tuesday, Madeline Holtznagel proved exactly why she caught the multi-millionaire's eye when she showed off her incredible figure in a sleek and plunging black dress. 

The 24-year-old looked sensational as she stepped out in one of her favourite frocks as she joined the likes of Martha Kalifatidis, Bella Varelis and her sister Simone Holtznagel for the Charlotte Tilbury cruise event on Sydney Harbour. 

Hello sailor! On Tuesday, Justin Hemmes' model girlfriend Madeleine Holtznagel (left) almost had a wardrobe malfunction in a VERY daring dress as she joined other models and Instagram influencers wearing barely-there outfits for a yacht party. Pictured with sister Simone Holtznagel

Hello sailor! On Tuesday, Justin Hemmes' model girlfriend Madeleine Holtznagel (left) almost had a wardrobe malfunction in a VERY daring dress as she joined other models and Instagram influencers wearing barely-there outfits for a yacht party. Pictured with sister Simone Holtznagel

Madeline, who hails from Wollongong, narrowly avoided a wardrobe malfunction at the event, with her plunging dress skimming her ample assets as she went braless. 

Her gown, which she has worn before at another event, also featured a daring leg split which helped put her trim pins on full display. 

Madeline finished her look with a pair of strappy black heels, a quilted Chanel shoulder bag and her blonde locks swept into an elegant low bun. 

Daring! Madeline, who hails from Wollongong, narrowly avoided a wardrobe malfunction at the event, with her plunging dress skimming her ample assets as she went braless

Daring! Madeline, who hails from Wollongong, narrowly avoided a wardrobe malfunction at the event, with her plunging dress skimming her ample assets as she went braless

Don't move an inch! Her gown, which she has worn before at another event, also featured a daring leg split which helped put her trim pins on full display

Don't move an inch! Her gown, which she has worn before at another event, also featured a daring leg split which helped put her trim pins on full display

Hot to trot: Simone meanwhile, who has since modelled for the likes of Playboy and Guess, looked flawless in a slinky black gown that featured a unique gold-rimmed cut-out over the bust

Hot to trot: Simone meanwhile, who has since modelled for the likes of Playboy and Guess, looked flawless in a slinky black gown that featured a unique gold-rimmed cut-out over the bust

Careful! However the blonde bombshell was seen walking on the yacht looking a little uncomfortable as she fumbled around with her top, trying to prevent a potential nip slip

Careful! However the blonde bombshell was seen walking on the yacht looking a little uncomfortable as she fumbled around with her top, trying to prevent a potential nip slip

Careful! However the blonde bombshell was seen walking on the yacht looking a little uncomfortable as she fumbled around with her top, trying to prevent a potential nip slip 

Dolled up: Madeline finished her look with a pair of strappy black heels, a quilted Chanel shoulder bag and her blonde locks swept into an elegant low bun

Dolled up: Madeline finished her look with a pair of strappy black heels, a quilted Chanel shoulder bag and her blonde locks swept into an elegant low bun

However the blonde bombshell was seen walking on the yacht looking a little uncomfortable as she fumbled around with her top, trying to prevent a potential nip slip. 

She was seen walking onto the yacht with her stunning lookalike sister Simone, 28, who rose to fame on Australia's Next Top Model back in 2011. 

The curvaceous beauty, who has since

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