I guess you could say I'm that Cosmopolitan girl!

The line reads like a self-aware, pop-cultural declaration of identity: the speaker aligns herself with the archetype of the “Cosmopolitan girl,” a shorthand for a modern, urban, fashion- and romance-savvy woman associated with Cosmopolitan magazine’s branding. The emphasis on “Cosmopolitan” suggests either a direct reference to the publication or to the broader idea of being worldly and socially fluent. The casual phrasing (“I guess you could say…”) adds a tone of playful concession, as if the speaker is acknowledging a label others might apply. As an anonymous quote, it functions more as a slogan-like quip than a traceable literary utterance.