Didn’t you know? It is all about sex!

Prosecutors recently found out that the largest room salon, or hostess bar, has been providing sex services to its customers to no huge surprise.

Proprietors of other similar enterprises were indicted on charges of tax evasion.

According to the bureau of violent crimes at the Seoul Prosecutors’ Office, a Kim and his brother, who run the YTT room salon and an S hotel were placed under arrest Sunday.

A Park, who was a nominal president of the operations, was indicted without physical detention.

The prosecutors said the Kim brothers were at the control of some 88,000 transactions involving sex and earned illicit profits estimated at 6.1 billion won ($5.7 million) between July 2010 and July last year in violation of the Sexual Solicitation Act.

As a result, they failed to pay over 3 billion won ($2.6 million) in pertinent taxes.

They also face charges of using accounts at the S hotel to settle these accounts to the tune of 2.8 billion won ($2.5 million).