Some of them do open on Sunday.
I'm not sure if they're open on Sundays but they open only at night.
They are open everyday and only in the evening after 6PM and closes at about 2AM. At the popular one opposite Monterey Hotel, try to queue, about 15 minutes before opening time. Mami Chan is my favourite and it is about 80m away on the same street.
Great place to chill out. Very sociable in atmosphere. Beer is available and typical Japanese food. A bucket list as you will not find similar setup, anywhere in Japan.
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