Kim Kardashian and Pete Davidson Reunion 'Not in the Cards' After Relationship 'Ran Its Course': Sources

Kim Kardashian and Pete Davidson's relationship didn't implode — it simply reached its natural conclusion, sources tell PEOPLE.

"They've definitely been slowing down," one insider says. "Things heated up quickly in the beginning when he could travel back and forth to see Kim and spend time with her, but his schedule has gotten so packed."

"Pete is still super bummed, though, about the breakup," continues the insider. "They really hit it off and had a ton of fun together, but it feels like it ran its course."

A second source tells PEOPLE that a reconciliation is unlikely to be on the horizon.

"It was an amicable split. They had discussed ending their relationship for a bit. It wasn't sudden," explains the source. "And it was a mutual decision. Getting back together is not in the cards right now."

News that Hollywood's favorite couple split came last week after Davidson has been on location in Australia for work. Kardashian, 41, and Davidson, 28, apparently attempted long distance for a few weeks before deciding to end the relationship.

A source first confirmed the breakup to PEOPLE on Friday, similarly citing both Kardashian's and Davidson's busy schedules.

The pair were together for nine months after they met around the time Kardashian hosted Saturday Night Live. On The Kardashians, the SKIMS founder was honest about how she connected with Davidson — by texting first with NSFW intentions.

"So, this is how it went down with Pete," she told cameras. "I did SNL, and then when we kissed in scene, it was just a vibe. And I was like, 'Oh, s---. Maybe I just need to try something different!'"

"But Pete does not come to my after-party — everyone was at my after-party — [he] does not give me the time of day, so a few days later, I called the producer at SNL and was like, 'Hey, do you have Pete's number? And they were like, 'Yeah,'" she continued. "I text him. I wasn't even thinking like, 'Oh my God, I'm gonna be in a relationship with him.' I was just thinking, 'Heard about this BDE [big d--- energy], need to get out there, I need to jumpstart my...'"

Kim clarified to cameras, "I was just basically DTF [down to f---]."

During the course of the relationship, Davidson got a series of tattoos seemingly for Kardashian including one that says "My girl is a lawyer" as well as the initials of Kardashian and her four children with ex Kanye West: North, 8; Saint, 6; Chicago, 4, and Psalm, 3.