Bringing B-day Cake in a Japanese restaurant

Hello, I'll be celebrating my birthday while in Tokyo when I go there in November. Is it alright to bring cake inside a Japanese restaurant? Is there a policy in these restaurants?
We're planning to eat in Nagatacho Kurosawa.

That would be rather rude I think. Why not go to a sweet parlour after dinner?

Bringing in your own food or drinks into a restaurant is usually prohibited. But it's very common to ask if they can arrange a birthday cake. Even authentic Japanese cuisine restaurants sometimes arrange Western style cakes for the birthday guest upon request. Discuss with the owner, or the conceirge at your hotel. Of course, if it's a Western style restaurant (such as French, Italian etc.) they can arrange a cake for sure, and probably even put a message on it.

They will either decline your request or accept with an extra charge.

You'll have to inquire with the restaurant directly.

http://9638.net/nagata/

As tokyo friend 48 says, they might decline. Or they might be able to accommodate your request, in which case I would expect them to charge a plating fee of a few hundred yen per person.

Oh, sorry for the lack of info. I never imagined that people might think they get free whole cakes at a restaurant. Of course, there will be a fee.

But on a related note, a lot of restaurants do provide free service for the birthday person, such as a small extra decoration on your paid dessert, or a free glass of a drink.

Thank you guys! I'll find out when I call the restaurant to reserve.