Japanese pop star Minami Minegishi made a tearful apology after a magazine reported she spent the night with a man.

The 20-year-old member of the juggernaut pop group AKB48 broke the band’s cardinal rule: No dating.

The Japanese Twitter scene exploded when the news surfaced that the starlet had disobeyed the rule, which resulted in the singer shaving her head as a form of self-punishment.

It is traditional in Japanese culture to shave one’s head as a form of contrition, BBC News noted.

Minegishi spent the night with her 19-year-old boyfriend, according to Japanese news reports, and she issued a video apology to the public in a clip that has been seen by millions.

She sobbed over her indiscretion in the clip and told her fans she doesn’t want to leave the group. Fans have allegedly dashed to her side, saying she should be able to lead a normal life.

The YouTube clip was made hours after a Japanese tabloid published pictures of Minegishi leaving her boyfriend Alan Shirahama’s apartment.

She decided to shave her long hair for her "thoughtless and immature” action, she said in the video posted on AKB48's official website.

"I don't believe just doing this means I can be forgiven for what I did, but the first thing I thought was that I don't want to quit AKB48," she said.

She sobbed throughout the video, sometimes bowing her head, and added: "If it is possible, I wish from the bottom of my heart to stay in the band. Everything I did is entirely my fault. I am so sorry."

AKB48 reportedly consists of about 90 girls who are supposed to portray an cutesy image known as “kawaii,” which is why the girls are not allowed to date.

Because Minegishi created a “nuisance to the fans," she has been demoted to a trainee as punishment, BBC News reported.

Some believe she went too far by shaving her head, due to the fact that the only rule she broke applies only to the band’s members.

One person took to Twitter, writing: "What's the point of this public execution show? It's like something from the war or a totalitarian state.”