Christopher Flowers is back in Tokyo, eyeing a second opportunity to make money from Shinsei Bank Ltd.

The founder of New York-based private equity firm J.C. Flowers & Co. teamed up with Ripplewood Holdings LLC founder Timothy Collins to start Shinsei back in 2000 and, with it, an era of customer-friendly banking in Japan. The investor group then sold most of its holdings for a multibillion dollar profit.

In November, Flowers reappeared, leading a group that includes Santander, Spain-based Banco Santander SA, Zurich-based Swiss Reinsurance Co., and Shinsei's senior management to offer $1.8 billion for a 32.6 percent stake in the bank. The group's tender offer closed Jan. 17, making the group the largest single Shinsei shareholder. The group will also buy ¥50 billion in new shares in March.