MUNICH - Glasses. Hoodie. Bulky body. No gold chains, mink coat or oversized sunglasses. This guy is a pale-faced nerd -- a geek. His name is Fabian Thylmann, and he just happens to be the biggest porn king of all time.

The German multimillionaire changed the porn sector worldwide by coming up with a totally new business model. On his website Youporn, millions watch sex videos on a daily basis. Thylmann is just 34 years old.

But for a couple of days now, the man German magazine Focus dubbed the “ruler of the kingdom of pleasure” has been in jail. He is awaiting extradition from Belgium, his adoptive country, to Germany where he faces charges of tax evasion.

Assertions that his company empire was evading tax on a grand scale were first made by journalists from the German newspaper Die Welt. Thylmann sued, and won. But prosecutors opened a case, and a Düsseldorf regional court is now hearing it.

Thylmann’s arrest has put a dampener on what has been so far an extraordinary career. Born in Aachen, in the state of North Rhine-Wesphalia, he wrote his first computer program at 18. By the time many are just finishing college, he had already bought several pornographic websites.

Today he heads the company Manwin, which he founded. Driven from hubs in Canada and Luxemburg, the company owns over 35 subsidiaries and brands such as Youporn, Brazzers, Pornhub, Tube8 and Mydirtyhobby.

Their products – sex videos catering to every imaginable fetish – may be filthy, but the business is lucrative. This is less because of that old saying "sex sells" than the fact that Thylmann has developed an effective porn business model for the Internet. This is the very thing that people in the music, film and news sectors are still trying desperately to figure out.

Users can consume all the pornographic content they want for free on the Manwin empire’s many web pages, a number of which rank among the 100 top-visited sites in the world. They are visited more often than the New York Times, for example, and are in the same league as Facebook, Google and Twitter.

How do the sites make money? The many millions of users watching the free movies are also seeing ads for paying porn sites that belong to the Manwin network. It is estimated that only one in a thousand users click on these. He or she then pays either a fee for one-time use or signs up for a porn subscription that offers better-quality, longer films than what is available free.

Sixty million users

Because of the millions of users on the free pages, one in a thousand is enough to make the Manwin concept pay big time. While the company doesn’t release exact figures, it is perfectly clear that over a half dozen of the world’s biggest free porn sites belong to it. These alone have around 60 million daily visitors.

Thylmann is said to have gotten 277 million euros from a hedge fund to finance his venture. The name of the fund has not been revealed.

Click by click, the young nerd from Germany has captured a whole sector. One result – marginal in the face of wider repercussions – is that urban customers who used to haunt local sex shops now prefer to spend their time surfing Thylmann’s websites, thus driving many of these small outlets out of business.

But more significantly: Manwin subsidiaries have for a long time been involved in every aspect of the porn business. From making movies to marketing them, they command the market and dictate the terms to the detriment of existing major producers in LA. The Manwin network and its 1,000 employees even manage classic erotic websites like Playboy -- which by comparison with the rest comes across as almost conventional.

For various reasons, Thylmann has until now maintained a low profile. He doesn’t believe in being a public figure. However, he does tweet regularly under the handle @ftyl, weighing in on such issues as the much-discussed law on mandatory use of condoms by American porn actors. He does not support the law.

He also has public Twitter exchanges with his brother Oliver Thylmann, also an Internet entrepreneur, about subjects such as how much content on an Internet page can be free and how much can be available only to paying users if the site owner wants to make a good profit.

Thylmann’s press spokeswoman Kate Miller, who works out of Canada, refuses all questions and requests from journalists for interviews with her boss. Our questions about the court case in Germany remained unanswered.

The structure of the Manwin company around the world is highly complicated and impenetrable for anybody on the outside. Along with a presence in Luxemburg and Canada, the network also works out of Cyprus, Germany, the United States, and Great Britain. German tax investigators have a mountain of work ahead of them – Thylmann’s sex videos may be widely available, but what’s behind them certainly is not.