Well spotted Fred. It's quite a feature with Virgin Atlantic aircraft. The "Scarlet Lady"carrying a Union flag is painted just behind the cockpit. The figure was designed by British artist Ken White, who modelled the motif on the World War II pin-ups of Alberto Vargas hence the naming one of the fleet Varga Girl.
Each aircraft has a name, usually feminine, such as "Ladybird", "Island Lady", and "Ruby Tuesday", but some are linked to registrations e.g. G-VFIZ became "Bubbles". There are a couple of commemorative names e.g. G-VEIL "Queen of the Skies", which was named by Queen Elizabeth II on 7 April 2004, in celebration of the centenary of the Entente Cordiale. An exception is "Spirit of Sir Freddie". An early Boeing 747 was named in honour of Freddie Laker, who helped Virgin Atlantic following the demise of his own airline Laker Airways. G-VFAB "Lady Penelope" had a special livery to celebrate Virgin Atlantic's 21st birthday.
Great thing Wikipedia.
tim