As far as I know, she doesn't. I think we need a tag to distinugish her, though, so I will add "Clerk Nagato" (長門店員 Nagato ten'in) which she is what she is listed as in the Lucky Star cast credits.
...isn't she just Nagato drawn in the Lucky Star style? How will you tell them apart without context? "nagato_yuki -nagato_yuki_(cosplay) lucky_star" would have covered it but alas...