What just happened? Japanese billionaire Yusaku Maezawa has an impressive background. With an estimated fortune of $3 billion, he's Japan's 18th richest person. He was also named as the first passenger on Elon Musk's SpaceX rocket flight around the moon a few months ago. Now, he holds the honor of having the most retweeted Twitter post---though there was a financial incentive on offer for those that spread his words.

Maezawa, who founded Japanese online clothing retailer Zozotown, posted a tweet on January 5 revealing that his firm had made 10 billion yen ($92.4 million) in sales over the holiday period.

To say thanks, Maezawa promised to give 1 million yen ($9,200) to 100 randomly selected people. For a chance to win the money, he asked users to follow him and retweet the post.

The message has now been retweeted over 4.5 million times. That puts it ahead of Carter Wilkerson, the Nevada teenager who was hoping for a year’s supply of Wendy's chicken nuggets (3.5 million retweets), and Ellen DeGeneres’ celeb-packed selfie from the 2014 Oscars (3.3 million). Maezawa now has the most retweeted post in Twitter history, while his follower count has jumped from around 500,000 to over 5.1 million in just a few days.

Last September, Elon Musk revealed that Maezawa had paid “a lot of money” to become the first private passenger on the Big Falcon Rocket, which is scheduled to take its lunar flight sometime in 2023. Maezawa said he would ask several artists to join him on the journey.

“They will be asked to create something after they return to Earth. These masterpieces will inspire the dreamer within all of us,” he said.