It started as a scoop in a weekly tabloid: an allegation that a middle-aged former boy star turned top television host had paid money to a woman for unspecified wrongdoing.

Other articles followed, claiming it was a case of sexual assault and stirring a wave of public anger not only at the former pedestrian, but also at his employer, a major TV broadcaster, for how it handled the situation.

On Thursday, the man at the center of the controversy announced his retirement, but the episode has already turned into a moment of reckoning. An international investor criticized the company, Tokyo-based Tokyo Television, and Japan’s biggest corporate advertisers lined up to boycott it. About 75 companies, including Toyota, Softbank and the local operator of McDonald’s, have pulled ads and sponsorships.

Not a single commercial appears on the station’s program; AD positions are now filled with unpaid public service announcements. Tens of millions of dollars in revenue are at stake as exasperated executives have called on Fuji TV to resolve the issue.

“We will stop placing ads with the company until a thorough investigation is conducted, the facts are clarified and appropriate measures are taken,” Takeshi Minakata, president of beverage maker Kirin, said in the statementwhich added that the company acted “on the basis of our human rights policy”.

Experts say the furor reveals a new intolerance for the sexual abuse he sparked earlier scandal. Two years ago, it was revealed that the founder of a top talent agency had been sexually abusing young men for decades. He died in 2019 without ever facing any charges, and corporate sponsors were accused of ignoring wrongdoing at the agency, Johnny & Associates.

This time the big corporations want to show that things have changed.

“The Johnny scandal marked a turning point,” said Ryu Honma, who has written extensively on the advertising and media industries. “The sponsors are guilty of complicity because of their inaction.”

The current case came to light in mid-December, when a weekly tabloid called Josei Seven reported that Masahiro Nakai, of the disbanded but still immensely popular group Smap, had become embroiled in “serious trouble” with a woman.

The article said Mr. Nakai, 52, paid 90 million yen, or nearly $600,000, to a woman who has not been publicly identified. Subsequent stories by other local media more clearly characterized what happened as a sexual assault.

Earlier this month, Mr Nakai admitted that an “incident” had occurred and that he had paid to settle it. He said he did not use violence in the encounter, which took place in June 2023, and that it made him feel justified in his decision to continue appearing on TV. There were no official investigations into the case.

Impotent criticism and Boycott AD forced him to reverse that decision. On Thursday, Mr. Nakai announced that he was retiring from entertainment and disbanding his talent agency.

“I don’t think this fulfills all my responsibilities,” he said in a statementpromising to “sincerely cooperate” in any investigation. “Once again I apologize from the bottom of my heart to another party.”

Anger also grew at Fuji TV, where Mr. Nakai was a popular show host. According to the tabloid article, a Fuji TV employee set up a meeting in 2023 between Mr. Nakai and the woman in the case.

Fuji TV initially issued a vague denial of “reports in some weekly magazines.” But it later said it was creating an internal committee to investigate allegations involving Mr. Nakai, as well as other media reports that it had long rewarded male talent by arranging matches with female announcers.

Fuji TV has come under fire for being slow to confront the situation head-on, and also for what it eventually did: a press conference open only to select media, with no live streaming or cameras allowed.

At a press conference last week, Fuji TV’s president said his company learned about the episode immediately after it happened, but did not disclose it.

“Ours at the time was not to make the matter public, but we respect the woman’s wish to return to work and prioritize her physical and mental recovery and protect her privacy,” said President Koichi Minato.

The press conference also came after the US shareholder, an investment firm called Dalton Investments, sent a letter to the management of Fuji TV Harshly criticizing the company’s failure to respond to – much less fix – its problems.

The situation with Mr. Nakai “reflects not only a problem in the entertainment industry in general, but, specifically, exposes serious deficiencies in your corporate governance,” the letter said. “The lack of consistency and, most importantly, transparency in both the reporting of the facts and the subsequent inexcusable lapses in your response deserve serious condemnation.”

The day after Fuji TV’s press conference, major Japanese companies began announcing that they were pulling their ads.

On Thursday, Fuji TV’s parent company, Fuji Media Holdings, weighed in. President Osamu Kanemitsu said it was “necessary to regain the trust of our employees, sponsors and spectators.” He announced that the company’s board had decided in an emergency meeting to set up an independent committee to investigate Fuji TV’s response.

“It took time for the realization to spread that I can’t look the other way,” said Mr. Honma, an advertising and media critic. “When the big customers start leaving, that brings action.”