Ms Left said the seller did not ask her any questions before she handed over the cat.
“I didn’t even say I was from a rescue (centre), she didn’t do any checks she was just very very happy to hand her cat over to me.”
The founder added that the seller told her “people had been having a go at her” for trying to sell the cat on the site, and she “did not see what was wrong with it”.
A statement from Vinted said the site “is not a place for the sale of animals, as stated in our Catalogue Rules”.
“Vinted takes action on reports of prohibited items on the platform, either through our own technology, such as software tools designed to detect prohibited listings, or through member reports,” it added.