Ginza's "Piranha" mama-san, the owner of a clutch of posh nightclubs occupying some of the priciest real estate on the planet, has been collared for allegedly failing to pay 240 million yen in taxes, Shukan Jitsuwa (4/24).

Seiko Sato, the 62-year-old mama-san nightclub industry insiders call "The Piranha" for her reputed talent at gobbling up whatever chance to pocket some money comes her way, has been placed under house arrest by the Tokyo District Public Prosecutors Office, which accuses her of withholding millions of yen belonging to the public coffers.

Also facing the same charge is 36-year-old Chiharu Nakanishi, the mama-san of one of Sato's clubs in the Ginza district of Tokyo and who appears to have been the key player in the case, albeit unintentionally.

"Rumors started floating around that the taxman had his eye on Sato in autumn last year. There'd always been something like that being whispered about her, though. She is, after all, the Piranha," a former hostess employee of Sato's tells Shukan Jitsuwa.

Sato got into the nightclub operating business about 30 years ago when she started a small club in an out of the way spot in Ginza.

"She met a shipping company boss while she was a hostess, and he set her up with her own club," one Ginza club owner recounts.

In the years that followed Sato opened one club after another, mostly in Ginza, but also in Roppongi, another popular entertainment district in the capital. She lived in a billion-yen palatial home in an exclusive part of Tokyo's Shinagawa-ku.

"She opened up all these different clubs," another nightclub operator tells the weekly. "She'd get funded by people like the operators of trust banks and the like. And she was a genius at finding herself guys with loads of money."

Nakanishi, meanwhile, was Sato's trusted lieutenant. But it was her 300 million yen in savings that allegedly led to the downfall of both the Piranha and herself.

"Nakanishi worked under the name of Sayaka Sakurai. She's famous for lying about her real age, and has been doing so since she started working as a hostess when she was about 17," a club insider tells Shukan Jitsuwa. "Nakanishi saved up as much as she could for years because she wanted to open her own bar. Sato eventually picked her up and got her to run one of the nightclubs she owned."

It was in this club that the taxman started sniffing around, laying bait aimed at catching the Piranha. One of the bar's managers introduced Nakanishi to a consulting company to help her look after her money, but tax inspectors already had their eyes on the consultant.

"While tax inspectors were looking into the affairs of the consultant, they learned that Nakanishi hadn't filed a tax return for 10 years. And they discovered she had 300 million yen in the bank," a club associate tells Shukan Jitsuwa. "Nakanishi was worried about having so much money in just one account, so asked Sato for her advice. Sato told her it wasn't good to keep all her money in the one account and she would be better off spreading it around more. Nakanishi then took all her cash out and was keeping it hidden in her home when the tax inspectors raided her and found the lot. The money trial eventually led them straight to the Piranha." (By Ryann Connell)