According to YouTube star James Charles, Ariana Grande is the "rudest celebrity."

The CoverGirl spokesperson slammed the Dangerous Woman singer in his most recent makeup tutorial video (also featuring YouTube stars Shane Dawson and Ryland), claiming Grande was rude for unfollowing him on social media last year.

In 2017, Charles attended one of Grande's concerts in Los Angeles. The pop star subsequently took notice of the vlogger after he shared a handful of videos and photos from the show on his Instagram Story.

She reportedly DMed him, thanking him for attending the show, and followed Charles on social media. However, their mutual relationship on social media was short-lived, as Grande quickly unfollowed Charles after fans pointed out his scandalous racist behavior.

In February 2017, Charles came under fire for being insensitive about his trip to South Africa, in which he tweeted, "I can't believe we're going to Africa today, omg what if we get Ebola?" In a tone-deaf apology tweet, he then referred to the continent of Africa as a country.

"[Ariana followed me] right after all my scandals started happening, so I was getting a bunch of really angry tweets from her fans that were really mad that she had followed me," Charles explains in the video, above.

After Charles realized Grande had unfollowed him "literally three hours after she had followed [him] in the first place," he messaged her, asking what he did wrong.

Grande then allegedly told Charles she didn't want to "disappoint" her fans by associating with him following his racial controversy, prompting the makeup artist to respond with a "strongly worded message" about the singer allowing her fans to "bully" him.

"'It really sucked that I was getting bullied by her fans and instead of ignoring it and building a friendship, she listened to them and unfollowed [me], which is saying that's okay to do...That was a disappointing interaction," he shared.

Though Charles says he ultimately had a "crappy experience with her," he "doesn't really have hard feelings about it."

As for Grande? The multi-platinum selling, Grammy-nominated artist has yet to respond to Charles' claims—she's probably too busy putting the touches on her forthcoming highly anticipated fourth studio album.

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