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.
Perry recently opened up about her longtime love in the November issue of W magazine.
"I actually am dating my crush," the 28-year-old gushed. "I had a crush on him for a long time."
"Of course," she said. "I really loved it. It was a new, fun, exciting journey. But I like how I am now, and I think all things happen for a reason."
Perry has also called her current beau a "genius" and told E! News, "I've been a fan of John's for years before I got to actually kiss him."
She added, "I've been such a fan, I think he's so incredibly talented and gifted and a genius songwriter. So to be a part of anything he was doing was just natural."
The two first went public with their whirlwind romance in summer 2012, which included a brief split in the beginning of the relationship, and have been by each other's sides ever since.