Alban McGill is a reluctant member of a family whose wealth is derived from the creation of an immensely popular board game. The three main plots of the novel (which are intertwined) concern his childhood romance with his first cousin, the question of whether the family will sell out to an American corporation, and the family secret that has greatly influenced Alban's life, none of which are remotely mathematical.
However, one of the main characters in the book is Verushka Graef, a mathematician specializing in the geometry of tilings and survivor of the 2004 tsunami, who happens to be Alban's current girlfriend. They met when (on a whim) Alban attended a lecture on game theory that was part of a math conference in the hotel where he happened to be staying. Nothing is said about her actual research, though she does try to have a discussion with Alban's family about the philosophy of mathematics via the question "Where are the numbers?"
However, as there is no real math discussed in the book, the primary interest of the book from the mathematical fiction point of view is in the presentation of the character of the mathematician.
Fortunately, she is not a stereotype but rather a fully fleshed out and interesting character. She is athletic, has spiky blonde hair which she sometimes dyes jet black. Alban's family also has an interesting reaction to the description of this woman who does math and climbs mountains, as if those three things are incompatible. VG (as Alban calls her) is thoughtful and smart, but not unbelievably so. Well, at least that was the way I saw her. The Guardian Review of the book describes her as more of a "dream girl":
Contributed by
Stuart Jeffries, Guardian
..a maths professor called Verushka Graef, whom Banks concedes is "something of a middleaged man's wish fulfilment" (she's blonde, brainy, fit, selfcontained, undemanding, likes oriental carpets, as does Banks, likes mountain climbing and casual sex, and is sceptical about commitment and having children).

It should be noted that this is by the same author who writes science fiction under the name "Iain M. Banks", whose novels include The Algebraist, described elsewhere on this website.
