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An insider tells E! News that the two are definitely headed towards an engagement.
"It's inevitable," the source tells us, adding that Perry and her leading man are "very serious."
Apparently, the couple is so smitten that friends and family wouldn't be the least bit surprised if Mayer popped the question.
"Everyone wants them to get engaged," the insider explained. "They are so perfect together."
Mayer has reportedly been spotted ring shopping for his pop star girlfriend, so perhaps it's only a matter of time before the two become future husband and wife.