Nina Melanie Rogers was a student who frequently crossed paths with Torchwood.
When Nina was looking for a room to rent, she encountered Jack and Gwen Cooper in the street near Jackson Leaves, where rooms had been advertised. Jack put her off by telling her, falsely, that the house was full. (PROSE: The House That Jack Built)
On another occasion, she had found a new boyfriend and was looking for a new apartment. In order to relax, she visited a toy store. The Vam chose this time to attack, eating both the store and the shoppers. Jack Harkness and Agnes Havisham were there to fight it off and Nina was one of the survivors. (PROSE: Risk Assessment)
With the assistance of Ianto Jones, Nina found a glowing book in the Cardiff University library, containing many recorded instances where Nina has met Torchwood, and promptly forgotten them again. When Ianto and Nina took the book back to the Torchwood Hub, they realised that the book had been looking for someone with excitement in their lives, influencing her meetings with Torchwood, then erasing the memories. With the help of Jack and Ianto, Nina deposited the book into the Rift, in the remnants of the SkyPoint building, causing it to collapse. Soon after, Gwen offered Nina retcon, which she took, forgetting her encounter with Torchwood, for the last time. (PROSE: Consequences)