Most people would use the phrase "open relationship", as in "I prefer to be in an open relationship", if that's the case, but she's so free and so open-minded that she prefers to repeat the word
polyamorous like a broken parrot, then explain at great length that she's actually single and would like to settle down in a monogamous relationship. But not yet, because she's so young and so free and so open-minded that she's desperate to look sexy and edgy.