Burgerking Russia already has a bit of reputation from some of its "creative" advertisements such as this one:

So it doesn't really come as a surprise that they also launched a cryptocurrency, Whoppercoin!
Whoppercoin was launched in 2017, by Burgerking Russia in partnership with Waves. The coins would be used to reward customers for each purchase of a whopper, and eventually to buy burgers in exchange for 1700 Whoppercoins or $26 USD. It's basically a blockchain rewards program.

Ivan Shestov, the head of external communications at Burger King Russia said: "Now Whopper is not the only burger that people in 90 different countries love – it's an investment tool as well,"
Customers could receive Whoppercoin tokens via their wallet and either sell or exchange them.
Trading never took off though.
Most people pointed out it was far cheaper to just buy a whopper than to obtain the coins. The coin isn't exactly dead, it is still listed on Yobit, but there hasn't been a trade for months!
Burger King Russia intially issued a supply of 1 billion WhopperCoins and even planned to release an app in the future.

So what happened then?
Well, basically nothing! The app was never released, and just weeks after launch, nobody was talking about it anymore.
I personally think this was just another big publicity stunt like some of their other advertisements to get a lot of attention in the media.
Maybe the Whoppercoin was a failure, and maybe it was a viral marketing success?
What do you think?