Karla Saaranen, a mysterious and beautiful Swiss woman that Lin meets early in his life in Bombay, turns out to be a very important figure in his adventure. Sexy, smart, and very popular, Karla is liked by everyone in the Bombay expat community, but doesn't seem to be too close to anyone.
This, of course, only makes Lin want to find out more about her. When he finally does, it hurts. She is similar to Khaderbhai in that Lin idealizes her completely, only to be utterly betrayed by her falseness.
You can almost hear the Disney princesses singing when Karla makes her entrance in the novel. And there's even cheesy pickup lines to match:
"I'm looking for your wings. You are my guardian angel, aren't you?"
"I'm afraid not," she replied, her cheeks dimpling with a wry smile. "There's too much of the devil in me for that." (1.1.152-53)
Karla just shows up, seemingly out of the blue, in time to save Lin from being hit by a bus. Of course, it isn't an accident at all, so her statement that she's got "too much of the devil" in her is not a joke. She's telling it like it is, but Lin is too infatuated to get it.
Okay, maybe she's a little shady. Karla is unable (or unwilling) to give her heart to Lin, and when he gets thrown into prison she disappears into thin air. It hurts his feelings, but he's trying to move on, when he finally gets word that she's chilling on a nearby tropical island. Of course he goes to visit, and Karla seems to let her guard down, revealing her true character to him.
The problem is that her true character is full of fear and terrible memories of a past where she was mistreated and raped—finally killing her rapist. She's in India because she is fleeing that past, and this might explain why she is just so unreliable when it comes to love and Lin.
Karla finally breaks Lin's heart when they are thousands of miles apart. She's disappeared, once again mysteriously. He's in the middle of Afghanistan when he finds out that, not only has she been the girlfriend of pretty much everyone he knows at some point in the past, but also that she isn't truly interested in him. She's just working for Khaderbhai, finding a foreigner to fulfill an important role on his mission to Afghanistan.
It's hard to say whether or not Karla ever truly had feelings for Lin, or for anyone for that matter. But her actions show that, even if she does have any love in her heart, it's so closed off that she can't really let it out. She tells Lin, "I'm cold inside, Lin. I like people, and I like things, but I don't love any of them—not even myself—and I don't really care about them. And you know, the strange thing is, I don't really wish that I did care" (5.42.217). Well… at least she knows herself, right?
We also noticed that Karla is pretty much the only woman in the novel with any depth. Lisa gets some airtime, and Kavita and Ulla are around, but Karla is the one that Lin pays attention to, the one whose thoughts and past matter. The fact that she's so cold, unforgivably cold, might have something to do with her femininity. Khaderbhai, on the other hand, is also a coldblooded traitor, but his manly-man ways somehow let Lin forgive him.