I had an idea for a story, but I think it would work better if someone else wrote it since I am not the biggest BK wota. This is supposed to be an anime where reactions are highly exaggerated.
An old Yakuza boss is getting ready to step down. He calls a meeting of his vast family. He has sired seven sons, each of whom has married into a different formally rival Yakuza clan and each one has as their eldest child a daughter. The boss says that he wants his granddaughters to form a counsel and run the family business.
Unfortunately, just the day before, the seven girls were scouted and offered the chance to form an idol group, so they decline being mob bosses.
At first, the boss thinks that they are joking since they do not look like idol singers. But when the boss realizes that they are serious he cries, so the girls feel sorry for him. They offer to be mob bosses by night if they can be singing idols by day.
And, thus the legend of Berryz Kobo - Yakuza Idols is born. The seven girls deal with problems like hentai producers, nosy wota, and rival gangs as only they know how! However, they may have met their match when another group tries to muscle in on their territory, another group of seven girls who call themselves Berryz Kamen.