Bringing along someone who knows what things are, or at least appears to, seems to be a good decision. His taste in food is clearly of the simple kind as he guides you to bread, sausage, lettuce, and tomato. Sandwiches it is.

You mention that you might want something to drink and perhaps some condiments for your sandwiches. He nods and brings you over to the wall of alcohol. You were thinking more along the lines of water or juice, but figure there's no time like the present to delve into the world of Korean beer and grab two large bottles.

He then wheels you over to the condiments. Mayo is easy enough to find, as is ketchup, but the mustard proves elusive. After a short search, a yellow bottle is located on a high shelf in the general vicinity of the mayo. Your guide assures you it is mustard. You:

accept his word and take one.

study the bottle more closely.

decide that mustard really isn't that important and move on to other things, leaving the bottle on the shelf.