Kylian Mbappé is nothing short of an artist with the ball. High-speed feints, receiving the ball at a dead sprint, explosive changes in direction: The striker has no shortage of skills to make a defender look bad. And he has taken the football world by storm. Nothing seems to be out of reach for the French national team player who, at only 19 years of age, has already won the French league championship twice and has been a World Cup champion since last summer. Time magazine recently featured him on its cover as one of its "Next Generation Leaders."

Having grown up in Bondy, a banlieue on the outskirts of Paris, this is a wunderkind with humble beginnings. It was here, at AS Bondy, that his career began, before he moved to the French Football Association's elite performance center at the age of 12. Things then started to move extremely quickly, and almost always with Mbappe's father Wilfrid and mother Fayza at his side. They don't just make sure that he is doing well, but also that business remains good. In fact, Mbappé, one of the most expensive football players in the world, has no player agent. When profiles are written about him, they often describe him as a grounded young man who hasn't forgotten his roots. But Mbappé is also well aware of his market value -- as Paris Saint-Germain learned during his contract negotiations in the summer of 2017.

Documents from the whistleblower platform Football Leaks that have been reviewed by DER SPIEGEL together with its partners at the European Investigations Collaboration (EIC), an international network of journalists, show a very different Mbappé -- one for whom enough never seems to be enough, a young man who hasn't been down to earth for some time now.

Mbappé played for AS Monaco for two years, winning matches practically on his own and shooting the team to the championship. This prompted the best clubs in the world to court Mbappé during the summer of 2017.

The Football Leaks documents indicate that Mbappé nearly switched to Real Madrid at the time. Ronaldo was his great idol as a youth, and the team was extremely interested in signing him, offering a transfer fee of 180 million euros. But his father Wilfrid was apparently worried about possibly unbeatable competition up front: The team already hadBale, Benzema and Ronaldo on its roster. At the beginning of August, Mbappé told Monaco that he had decided to sign with Paris Saint-Germain.

PSG had also agreed to pay 180 million euros for Mbappé, a figure so high that AS Monaco couldn't refuse the transfer. The team agreed. In mid-August 2017, Kylian and Wilfrid Mbappé met with PSG Sporting Director Antero Henrique. They demanded a total of 55 million euros: 5 million for the signing bonus and a 50-million-euro salary for the duration of the five-year contract. Net. PSG agreed, making Mbappé one of France's highest-paid football players.

But as the Football Leaks documents show, there was a whole list of other demands that PSG rejected.

If, for example, Mbappé were to win the Ballon d'Or, he wanted to automatically become the highest-paid player on the PSG payroll -- meaning he would be making even more than Neymar. Paris Saint-Germain refused.

Mbappé also demanded that the team make a private jet available to him for 50 hours per year, another clause that didn't make it into the contract. But he does receive an allowance of 30,000 euros per month so he can pay his personal staff: a caretaker, a driver and a bodyguard.

His family was also apparently deeply concerned about the possibility that PSG would be found in violation of the Financial Fair Play rules established by UEFA. The rules prevent teams from spending more than they take in and Mbappé's club had just signed Neymar for 222 million euros. Mbappé's family asked about monetary compensation should PSG be banned from the Champions League, a penalty reserved for the most severe violations of the FFP rules.

Furthermore, permission was requested for Wilfrid Mbappé to be present during team practices. And for him to conduct additional training sessions with his son at the Paris Saint-Germain facility.

Once the details between Mbappé and PSG had been ironed out, it was time for the contract with AS Monaco to be negotiated. The offer from Real Madrid served as the basis for those talks: 180 million euros. In the end, the second-most expensive player in the history of football was loaned to PSG for the first year at no cost, with an exclusive option to buy after that period elapsed.

The transfer of Mbappé, a player brought up in its own academy, secured for AS Monaco what was likely one of the most profitable deals in the history of commercial football. And the greatest beneficiary was Dmitry Rybolovlev, the Russian oligarch who has pumped over 300 million euros into the club since 2011. He has already written off half of that money. Thanks to Mbappé, as the Football Leaks documents show, he will be the recipient of 124 million euros. Neither Rybolovlev nor AS Monaco nor PSG responded to requests for comment on the Mbappé transfer from the reporting network EIC. The player himself likewise withheld comment.

It shouldn't go unmentioned that in the end, one of the most influential player agents in the football industry also found a place at the table, his hand outstretched. It was the Portuguese agent Jorge Mendes, who almost by divine right, always turns up when vast quantities of money are at stake. On the morning the contract was signed, on Aug. 31, 2017, at 7:52 a.m. local time on the Côte d'Azur, Daniel Bique, chief legal counsel for AS Monaco, added the Portuguese's name to the transfer agreement. Mendes' fee: at least 7.25 million euros.

But for what?

It seems possible that his contribution was that of playing up speculation that Mbappé would be transferred to Real Madrid as a way of driving up the player's price. There are documents in the Football Leaks trove that would seem to hint at such a conclusion.