The energy drink was created by British entrepreneur Jonnie Shearer in 2004, whose plan is to make Pussy a brand in the manner of Virgin.
Until now, the brand has mainly been the preserve of nighclubbers and celebrities.
This year the drink extended beyond its celebrity status, when it achieved listings in Tesco and Selfridges. The brand is also sold on Virgin Trains.
Pussy is made of a blend of grape juice, Mexican limes and lightly carbonated water. These are mixed together with granadilla and lychee flavours, which are in turn mixed with six botanical herbs.
It is selling itself as a 100% natural energy drink that is used as a hangover remedy.
The brand – which is stocked in 3,500 outlets – now plans to expand to overseas countries, including the US and Russia.
It is unclear how much the two Bransons are investing the brand. Holly is currently involved in the launch of Maverick, the digital title launched on the iPad.
Virgin is to extend its brand into consumer magazines, with the launch of a title to be led by Holly Branson, daughter of the company's founder.
Pussy is sold in 250ml cans and is priced at £1.34 in Tesco.
Founder Jonnie Shearer said: "Seven years into marketing the brand through word of mouth, members’ clubs and private events from Monaco to LA, we’re proud to be recognised as a major player in the energy drinks market. My plan is to make Pussy a lifestyle brand, like the Virgin brand that I have admired so much over the years."
To showcase the funding by the Branson children, 3,000 cans of Pussy were transformed in to an 8m-wide and 1.5m-high 3D sculpture by installation artist Emma Winter.
The brand’s strapline is: "The drink is pure, it’s your mind that’s the problem."
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