No, the restaurant is located in the back of the sauna area and you can't enter the sauna area with out your uniformt. There's an H mart and Korean restaurants in the same shopping center
Technically you cant use the restaurant in the spa without paying admission and switching to their mandated uniform so i would recommend you try the other restaurants in the same plaza. The choices at the korean restaurant that is about three shops away has the same selections. If you decide to use the spa and eat there you will scan with your bracelet which they charge everything and you pay the final charge when you check out.
The sauna does not make sense, but there are other places nearby
The entry fee includes the restaurant but no you can't
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