Answer by taking a quote from the following article:

A Bond girl is a character (or the actress portraying a character) who is an attractive love interest and/or female sidekick of James Bond in a novel, film, or video game. Bond girls occasionally have names that are double entendres or puns, such as Pussy Galore, Plenty O'Toole, Xenia Onatopp, or Holly Goodhead, and are considered "ubiquitous symbol[s] of glamour and sophistication." There is no set rule on what kind of person a Bond girl will be or what role she will play. She may be an ally or an enemy of Bond, pivotal to the mission or simply eye candy.

Roald Dahl said that when writing You Only Live Twice, he was advised to use three Bond girls: The first should die "preferably in Bond's arms" early, the second a villain whom Bond seduces before she dies in an unusual and gory way midway, and the third survives to the end of the film. In several, the Bond girl is revealed, after her tryst with Bond, to be a villainess. Examples are Fatima Blush (Barbara Carrera) in Never Say Never Again (1983), Elektra King (Sophie Marceau) in The World Is Not Enough (1999), and Miranda Frost (Rosamund Pike) in Die Another Day (2002). The Dalton films of the 1980s introduced the "Bond woman", who is equal to and challenges Bond, but he remains the heterosexual hero; they are depicted with Dalton and later Bonds and their cars and gadgets, implying that all are possessions that Bond can use and dispose.  As of 2013 there have been only two films in which James Bond falls in love with the Bond girl. The first was On Her Majesty's Secret Service (1969), in which Countess Tracy di Vicenzo (Diana Rigg) marries Bond but is shot dead by Irma Bunt and Ernst Stavro Blofeld at the story's end. The second was Vesper Lynd (Eva Green) in Casino Royale (2006). Bond confesses his love to her and resigns from MI6 so that they can have a normal life together. He later learns that she had been a double agent working for his enemies. The enemy organisation Quantum had kidnapped her former lover and had been blackmailing her to secure her co-operation. She ends up actually falling in love with Bond, but dies, as Quantum is closing in on her, by drowning in a lift in a building under renovation in Venice.  With the exception of these two doomed Bond girls, it is never explained why Bond's love interest in one film is gone by the next, and is never mentioned or even alluded to again. This is not always the case in the novels, which do sometimes make references to the Bond girls who have appeared in previous books. Tiffany Case and Honey Ryder are revealed to have married other men (in From Russia With Love and The Man With the Golden Gun respectively), and in Doctor No, Bond briefly wonders about Solitaire. In Licence Renewed it is specifically noted in an epilogue that Bond and Lavender Peacock stopped seeing each other after a brief romance. A unique case is Mary Goodnight, who appears in the novels, On Her Majesty's Secret Service and You Only Live Twice as Bond's secretary, before becoming a full-fledged Bond girl in The Man With the Golden Gun.

Which movie was she in?
You Only Live Twice,