At times, Ruta and Rojack seem so similar that they might as well be soulmates. Overwhelming lust? Check. Oodles of ambition? Check. A talent for manipulating others? You betcha. Despite this, Rojack sees Ruta exactly how he sees the other women of the novel: as tools to reach his own ends.
Their brief sexual liaison actually tells us a lot about both characters. On the one hand, it highlights Rojack's overwhelming lust—he has literally just murdered his wife yet still needs some T.L.C.—but the more surprising thing is that Ruta is really into it, telling him that he is "absolutely a genius" (2.33) when they're finished. However, we also learn that Ruta has some dark sexual preferences of her own when she admits that she "goes out to look for men who will beat" (2.67) her when she drinks. Maybe a guy who's just killed his wife is the next best thing?
It shocks Rojack to discover that Ruta—like Cherry—is Kelly's mistress. This is where Ruta's ambition comes into play: She claims to have "a chance he will marry [her…] if […] she can play the cards" (8.252) right. In many ways, she's a lot like Rojack was when he met Deborah: eager to marry into wealth and power.
What Ruta doesn't realize, however, is that she'll have to pay a steep price. Rojack knows this all too well, and An American Dream represents his escape from this world of high society. We never learn what happens to Ruta, but we're willing to bet that she ends up getting far more than she bargains for as she makes her way up the social ladder..