Kim Kardashian is 'head over heels' for Pete Davidson: 'She is happiest'

Kim Kardashian and Pete Davidson  is one adorable couple in tinsel town!

The lovebirds, who recently made a trip to Tahiti, are getting serious about one another and are reportedly planning their future.

"It's their first summer as a couple and they are having a blast," a source tells PEOPLE. "Pete has an intense work schedule starting later this summer, [so] they are trying to enjoy as much [time together] as possible right now."

The insider adds that "it was a very romantic trip" for both the mother-of-four and the comedian.

"They were in Tahiti for several days without the kids," the source continues. "Kim is head over heels. She can't get enough of Pete. He treats her so well."

Adds the insider: "He is protective, super supportive and just a great guy for Kim. She is the happiest."