The Shawn Mendes and Camila Cabello summer romance is in full swing—and E! reports it isn’t going to die down anytime soon. The longtime friends turned new It couple were documented kissing two separate times in San Francisco this weekend. TMZ got a photo of them on Saturday smooching at a coffee shop:

And that’s just the latest public display of their summer fling. They’ve also held hands in front of paparazzi after brunch in Los Angeles, and Cabello has been going to so many of Mendes’s shows. It seems like they’re all in because they are, a source explained to E!.

“It already feels to them like they’ve been together for a lot longer than they have,” the source said. “They’ve known each other and been a part of each other’s lives for a while so it’s all very natural and moving quickly.”

The chemistry has always been there. The timing? Not so much. Cabello just recently ended her year and a half-long relationship with dating coach Matthew Hussey in June. Mendes, meanwhile, was last linked to Hailey Baldwin last spring before she and Bieber got back together in June.

With Cabello and Mendes, “the timing wasn’t right before but it is right right now,” E!’s source said. “They are going for it without holding back. This step in their relationship is exciting for them both. They haven’t wanted to be apart at all. It’s 24/7 and all out at this point.”

Cabello has been purposely following Mendes on his tour this summer. “Neither of them want to be away from each other,” E!’s source said. “She has the opportunity to be there with him and she’s taking it.”