Remember Ariana Grande's life coach/choreographer who allegedly quit because of the singer's alleged diva behaviors? Well, it turned out that he is not just an ordinary former employee working for the pop star; he is actually Grande's longtime best friend Isaac Calpito, according to J-14 magazine.

A source told New York Post that the life coach (Calpito) quit his job because he could no longer deal with the singer's bad attitude."He just couldn't take it anymore," said the insider. "Everything people are saying about her is true."  

Calpito, however, took to Twitter to shut down claims that he was involved in recent media reports bashing the former Nickelodeon star.

"There have been a lot of lies and false accusations about me. I have kept quiet and classy till now because that is the kabbalistic way," tweeted Calpito. But now the false rumors have simply gone too far."

He confirmed in a follow-up tweet that he resigned and was not fired from his job, and even he no longer works for Grande, he still wishes the best for her ex-bestie. "I wish Ariana the BEST and even if I had a story to sell....I wouldn't," he wrote.

"I am very appreciative of the time I spent with Ariana and will always have fond memories of our work together. I will always be a fan," Calpito added.

The "Problem" hitmaker called Calpito "my best friend" on an Instagram post she shared as recently as five months ago, so fans have started to wonder what had really happened between them.

A source close to the "Sam & Cat" alum told Radar Online that there "were numerous complaints by many women working around the team" against Calpito for "inappropriate behavior."

"He was suspended, and then they did a thorough investigation with an independent investigator," the source continued. "There was a lengthy investigation report, and once the results came back, he resigned. Basically, the result of the investigation demonstrated there were serious issues, and he chose to step down."

But Calpito told Radar Online that "These accusations are completely untrue. They're completely false."

"It stems from a group of people in Ariana's camp that wanted me out for various reasons. They made it very uncomfortable for me, and so I resigned," he explained. "Basically, it's slander and defamation of character, what they're doing to me. It's incredibly transparent. And not classy. I'm not there anymore. I'm very happy to be not there anymore. I think her behavior speaks for itself."