Plenty of places to eat, some configured as you've described. It's likely best if you took a stroll around the area and inquired directly with places that you're interested in.
There are great brunch spots on the square, every now and then there are discounts with church fliers etc. A few of the restaurants have private party rooms and banquets rooms as well. If your looking for like a speakeasy type place with super private back secret room, try Muss and Turners in vinings(Eleanors)
There are multiple restaurants within the square and each location offers may very..
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