Ninja restaurant Akasaka with children

Hello

With our children (8 and 11), we would like to book at the Ninja restaurant in Tokyo
With children it's indicated that booking is only possible at 5 pm on week days
But do you know if reservtion time could be later on Saturday or Sunday?

Thanks

What I read off from their website in their FAQ in Japanese about whether children can enter the restaurant, their reply is:
"Yes, of course children are welcome. On weekdays, however, as there are many other guests from business entertainment who are a bit tipsy, so children can stay in the restaurants until 19:00. Anytime is OK on Sundays and national holidays. But please note that it is dark inside the restaurant and our ninja carry dangerous weapons. In order to avoid children getting injured in the aisles, please make sure adults accompany children when they leave the dining rooms, such as going to the restroom."

http://www.ninjaakasaka.com/qanda.html

Whoops, "guest from business entertainment" didn't quite sound right, does it.

I guess what they mean is that since Akasaka is a business district, on weekdays they get a lot of groups of businessmen who are dining there, in the later hours, so that they are asking that family guests with kids stay only from 17:00 - 19:00 hours.