They're usually seen in demure frocks and fascinators, as is fitting at official royal events.
But last night, Princess Eugenie, 25, and her sister Beatrice, 26, swapped their usual modest looks for racy rock chick style as they headed to a fancy backless prom dresses uk party at Ours nightclub in London.
Beatrice arrived hand-in-hand with her long term boyfriend Dave Clarke wearing a thigh skimming black mini dress with a studded leather gilet.
Princess Beatrice arrived hand-in-hand with her boyfriend Dave Clarke for a fancy dress party at Ours nightclub in London
She appeared to have crimped her flowing red tresses for the occasion to give a more voluminous look.
And she completed the ensemble with a pair of gold t-bar sandals.
ShareThe royal kept her make up relatively natural but opted for smokey eyes and heavy black liner to complement her gothic look.
Boyfriend Dave was equally in keeping with the rocker vibe, wearing a Guns N' Roses t shirt with a sleeveless leather jacket.
Eugenie's coat fell open as she walked to reveal she was sporting a pair of racy suede over-the-knee boots
Dave, who works for Sir Richard Branson's Virgin Galactic space programme, swapped his normal preppy chinos and shirts for a pair of grey skinny jeans and black boots.
Meanwhile, Princess Eugenie initially appeared to be more covered up than her sister in a black belted coat with leather sleeves.
However, her coat fell open as she walked to reveal she was sporting a pair of racy suede over-the-knee boots.
Clearly aiming to vamp up her style, she added a slick of red lipstick.
Crowds spilled out at the end of the fancy dress party but the royal sisters weren't ready to go home yet
Beatrice's boyfriend Dave Clarke was equally in keeping with the rocker vibe, wearing a Guns N' Roses t shirt with a sleeveless leather jacket
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