Who Took Lolita's Innocence?

In "Lolita", Humbert Humbert looks at young Dolores Haze and sees a sultry nymphet. Every innocent action little Lo does in front of him is unintentionally seductive. "She grasped it and bit into it, and my heart was like snow under thin crimson skin, and with the monkeyish nimbleness that was so typical of that American nymphet, she snatched out of my abstract grip the magazine I had opened (pity no film had recorded the curious pattern, the monogrammic linkage of our simultaneous or overlapping moves) (Nabakov 58). Humbert's will power prevented him from damaging Lolita's innocence. Despite his self control, Lolita comes back from Camp Q, totally different. Her sexual prowess is not hidden within her but she openly shows it. Before she left for camp, Lo would never be sexually promiscuous towards Humbert Humbert intentionally. However, now it seems that she is flirting with him and seducing him. One might wonder if her "innocence" was taken away at Camp Q, or that her innocence was not taken away at all and she pretended to be a sultry, experienced little nymphet. One may wonder if her promiscuousness was a ploy for Humbert to think her innocence was taken away from her already so that he would not feel guilty of actually taking her innocence. And how are we supposed to believe Lolita? Have we ever been given a reason to believe her? Because the story is not told from her perspective we are unable to fully know if she ever told the truth. Was Lolita's innocence taken at Camp Q? Or was it taken by Humbert Humbert?