And now they're engaged.
"The combination of a girl who is yearning to be loved and mixing it with a guy like Pete creates this intense relationship that is moving a million miles a minute", the source said.
Blonde bombshell Ariana was spotted wearing a ring at iHeartRadio and 102.7 KISSFM's Wango Tango concert in Los Angeles earlier this month.
"They are a flawless fit. They are not rushing to get married", one insider says. "Their friends are really excited and supportive", another insider told Us Weekly. "For both of them, this relationship is heaven compared to their past relationships and they're just clinging to that heaven and thrilled about it". "Their moms have met".
They later made their relationship public on Instagram and have been using the social media platform as a vessel for their love and affection towards one another ever since, with Pete even showing off two new Ariana-inspired tattoos. Grande also recently shared a photo of the couple. Grande has since deleted the tweet.
The pair, both 24, had confirmed that they were dating in May, shortly after Grande broke up with her ex Mac Miller.
Davidson dated Cazzie David on and off for two years until May.
Grande is preparing to release her new album Sweetener in August, while Davidson stars on SNL. He joined the long-running sketch show in 2014.