Vivian is Arthur Widmore's third wife, and at the time of the book has been married to him for 5 years. A widow from her previous marriage to Monty Alban, Vivian is about 57-58 years old, with dark wide-set eyes, and thick black hair with a touch of grey. Like her husband, Vivian also likes her drink, and the two seem to indulge in alcohol throughout the book.
The most damning account of her character comes from her step-son, Clifford Widmore, who describes her as a "loose cannon and a bit of a hysteric". He also refers to her as a "slut", and implies she may have married Arthur Widmore for his fortune. This led him to hire another private investigator as well as Paul Artisan, named Pru Cunningham, to follow Vivian's movements and photograph her affairs.
Indeed, Vivian does attempt to seduce Paul Artisan in the book, and is later revealed to have been having an affair with "Mr. Thursday".