[It might give the place an air of (supposed) legitimacy.
Of course, once arriving the bottom of the stairway, the entrance to the dungeon workspace would not actually have any pesky signage that would alarm the young ladies or make them hesitant in any way . . . it might just be something inconspicuous, such as: No Cell Phones Allowed Beyond This Point. ((((Shhhh.))))]
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Gee, that’s not a bad idea! I could even recruit from within to have it built!
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