Supposedly the new thing in Japan is restaurants with themes. The quick explanation would mean a restaurant that makes you feel like you are in Disneyland.

For example there is the Seiryuumon chain each of which has a slightly different theme.  There are 2 or 3 chains of prison themed restaurants where you eat inside prison cells.  There are Arabian themes and Thai themes and even a Gothic Church themed restaurant.  One thing they pretty much all have in common is they are party restaurants.  Places to have a good time and get loud.

One of the newest is called Ninja and for lack of a better description has a Ninja theme.  The entrance is a maze, the inside looks like an old Japanese village I guess and the waiters/waitresses are dressed as ninjas.

Unfortunately that was the end of it.  It was a sedate place.  Nothing happened.  The music was a kind of new age mellow lull you to sleep selection.  There were no events, we could not hear anybody else talking which might be good if it was supposed to be a quite dinner for  2 place but we were there with 7 people.  On top of which the prices were high.  It ended up being about $50 each.  And the food was not bad at all but nothing special either.

Ultimately it was fairly disappointing.  I recommend you avoid it.