I know exactly who you are talking about, but couldn't remember her name, had to resort to the wiki for it. So ashamed.
It's Junko/Kelly depending on the version.
According to the wikia: Kelly's name was never once spoken during the series. Rather, it was only ever made known through a casting sheet released online at the time of the show's premiere.
Anyway I pass my question asking as I had to use the wiki to get the answer.
