As Rod lead Penny down the stairs of the club, a man in beige chinos dropped his trousers to show his bare bottom.
The couple were seen laughing before they quickly moved past the man alongside their friends.
They then got in a car, and swiftly departed the venue.
Former model Penny wowed in a floral purple mini dress teamed with matching stilettos.
Many fans were quick to wish the couple a happy anniversary, with one writing: “Happy Anniversary! Beautiful couple!”
The couple have also been out on several occasions to celebrity hotspot Annabel’s in Mayfair over recent weeks.
Penny revealed she and Rod were happy to finally be allowed back “on the town” as they slurped cocktails together at Annabel’s member’s club two weeks ago.
The star shared a sweet photo of her and Rod at the bar enjoying a much-needed refreshment as they celebrated their “hair cuttings”.