I am certain if you told them there was a birthday celebration in your party that dessert would be complimentary for him or her. They don't come out and sing the happy birthday song though...
I would not associate this place with the word "specials" if that word means "discount", if it means some type of menu item not listed I assure they will do anything requested for premium fee. However it feels like a strip mall restaurant with high ceilings and linen, the tables look out onto a street which is only 20 feet away..
Will call the restaurant to discuss what you want for the Birthday Dinner Specials, like number of people, what you like and whether the restaurant can make a special menu for you and the guest or guests.
They have a chef's choice maki, sashimi, nigiri plate which surely could be jazzed up for a birthday if asked.
If you had other specials in mind for the guest of honor, the servers have been accommodating of substitutions in the past. Specifics should probably be called ahead.
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