Is a chocolate product sold in Britain and the Anglosphere and produced by Nestlé which has been for some time. It's basically a normal sized bar of white chocolate all divided up into chunks in the manner of a Dairy Milk or a Bournville. It's also sold in continental Europe as a "Galak" which is a rather less appetising name than Milkybar, but it's the same thing.
What you probably don't know is that the Milkybar is widely considered in some narrow circles to be a cursed confectionary, which has, since 1937, left a trail of death, corruption, and fat bastards in its wake.
The story goes that when it was first introduced in 1937, a Nestlé R&D man accidentally fell into the vat where the first batch was being mixed. The vat was slick-sided and although the molten chocolate was not deep enough for him to drown in, and not hot enough for him to burn to death, it was hot enough for him to starve. His colleagues tried to save him, but a visiting Procter & Gamble executive, being in league with the Antichrist, hid every rope in the factory, so the poor man, who is known only as Clément Olivier Noyé, starved to death, and although his remains were sieved out before the batch could hit the market, in his dying breath he cursed the bar forever. This began the tale, which has been systematically hushed up by Nestlé executives ever since.
In 1949, a baker named Thomas Kolb from Fulda in Germany bought a Milkybar as a special treat for his nine year old son, Franz. The son acquired a crippling white chocolate addiction and died at 35 years and 35 stone later on. He was so fat that he required a crane to be lifted in and out of his bed and a coffin the size of a Volkswagen. When he was being lifted out his hospital bed after his demise, the crane broke and his corpse crushed a nurse to death.
In 1961, the Milkybar kid advert campaign began. The Milkybar kid is the usual mascot and what it is best known for, an angelic looking small boy (for the most part) who appeared in its advertising. What they don't tell you, though, is that most, if not all of the Milkybar kids have been corrupted by the bar's evil, and several have died of obesity-related illnesses, as Nestlé used to send them a crate and a half of Milkybars each year as a payoff to feed the cocoa-addled monkey on their backs. One of them, Sam Read, grew up to form a grindcore band in Manchester called Foetal Juice. The incredibly squickiness of the music was, he told me when I met him in Bloodstock in 2012, the only way he could keep at bay his Milkybar cravings. Another Milkybar kid is said to have been a serial killer in Rzeszów in Poland in the 1990s.
In 1970, in Nottingham, a Heather Barton from the village of Ravenshead nearby was arrested for prostitution and when questioned, said she did it to feed her Milkybar habit. A local boy had hooked her on Milkybars while still at primary school. Allegedly this is not uncommon, and "bar whores" can be found in every major municipality where Milkybars are sold. The only reason it has escaped the War on Drugs was that Nancy Reagan was said to be addicted to them.
In 1999, a map was made by a Chief Inspector Stanley Shufflebottom of the Metropolitan Police in London correllating the rate of arson and homicide by a stranger unknown to the victim across the city with places where Milkybars are sold over a 30-year period. There was a 99.4% match. However the map was suppressed.
In 2010, the Pike River mine accident in New Zealand cost the lives of 29 miners. One of them was rumoured to have a Milkybar in his lunchbox, and the most recent Milkybar Kid was, in fact, from New Zealand.
The polar opposite (and nemesis) of the Milkybar is, of course, the Lindt 99%. This is a ridiculously strong dark chocolate which is 99% cocoa and thus too dry for human consumption. This is because it is not meant to be eaten. It is basically a ward. The presence of Lindt 99%, for reasons unknown, suppresses the addictive and corrupting qualities of Milkybars, and a chunk of it can help alleviate Milkybar withdrawal symptoms. Furthermore, being in the presence of a Lindt 99% lowers your risk of heart attack and stroke by up to 3%. It is also shown that where Milkybars are sold, if Lindt 99%s are sold in the same store, those who work at, and shop at, that store generally have better luck all round in their lives than in stores where Milkybars alone are sold. It is rumoured that this is because the Lindt 99% was the product of divine inspiration. However, on no account allow a Lindt 99% to come into contact with a Milkybar. According to eldritch chocolatier legends, putting the two in direct content can cause a thermo-bar-ic explosion, much like matter and antimatter, and that in 2002 one happened in Zurich at a bus stop. The mess was considerable, and hundreds of innocent bystanders suffered significant weight gain as a result of the fallout of microscopic sugar particles. However this is never spoken of, and Nestlé denies all knowledge to this day.
(By the way, all the above is totally false. Apart from the bit about the Milkybar Kid who grew up to be in a grindcore band called Foetal Juice. That actually happened. I met him.)