Yoshi first met the nightclub owner once known as "the king of Roppongi" in 2011. Yoshi (not his real name), a building engineer from Utsunomiya who had emigrated to Nigeria extra-legally a year earlier in search of work, was swimming at the Transcorp Hilton, where Nigeria's power brokers stay when they're in Abuja, the capital.

He was with a friend, a Nigerian returnee from Japan, and together they approached a Japanese woman they had been surprised to spot. She was visiting with her Nigerian husband, she said. Her biethnic children splashed in the pool nearby.

The husband, Gilbert Otaigbe, told Yoshi he was in the hospitality business. He said he'd been arrested in 2010 for violating Japan's vice laws. Ever since, he'd been wanting to relocate to Nigeria. He talked to Yoshi's friend, and confided that he rarely left his house in Japan anymore. The police were waiting for him, he said. He couldn't be too careful.