Rose’s initial reaction was one of revulsion.
“Ugh! What the hell IS that thing?”
“She’s not a thing,” the Doctor corrected. “She’s a Novocholian; her name is Errensia. She doesn’t think you look very nice either, but she’s too polite to say so.”
Chastised, Rose apologised. “Sorry, I was taken by surprise, I’m not used to meeting people who’re so… different. Where I’m from, the only things with that many legs are… Well, they’re sort of creepy and not intelligent. Most people don’t like them.”
Travelling with the Doctor, she’d have to learn that having two legs was not universal.