Valeria is Humbert's first wife, whom he married in an effort to cure himself from his desire for young girls. He believes that some home-cooked meals and the routines of domestic partnership will wean him from his addictions. Valeria does, notably, remind him of young girls, as he explains:
Although I told myself I was looking merely for a soothing presence, a glorified pot-au-feu, an animated merkin, what really attracted me to Valeria was the imitation she gave of a little girl. (1.8.1)
She later leaves Humbert for a Russian taxi driver, which really ticks Humbert off, bringing out his violent side. Valeria later dies (in childbirth, like Lolita) in California, where she and her husband participated in some strange experiments in Pasadena.