It all started when a young model, Sunnaya, took to Instagram to share a creepy DM exchange with Marcus.
The well-known photographer had posted a callout, looking for nude models to shoot with.
The screenshots showed that Sunnaya replied saying she was keen to shoot, but wasn't comfortable with nudity.
In response, Marcus snapped back "It's 2k then." When Sunnaya relented saying she would shoot nude but not send him nude screenshots in advance, the conversation took a turn.
Marcus can be seen telling Sunnaya he "needs to see if she's worth it," among other shocking messages.
Fashion Instagram account @dietprada was quick to ask Ariana Grande and Kim Kardashian to address the controversial messages, as both celebs had worked with him in the past.
They both came through, leaping to the young model's defence.
"I have been reading all of the messages and stories from women regarding inappropriate and inexcusable behavior of a photographer that I have worked with in the past. "My own experiences have always been professional, and I am deeply shocked, saddened and disappointed to learn that other women have had very different experiences" Kim posted on her Instagram stories.
She continued: "I stand in full support of every woman's right to not be harassed, asked or pressured to do anything they are not comfortable with."
Meanwhile, Ariana posted to her own Insta story "Please do not shoot with photographers who make you uncomfortable or make you feel like you need to take your clothing off if you don't want to.
"If you want to, sick. but if you don't, please don't. if they tell you you have to pay more money if you're clothed that's f--ked and i'm sorry that has happened to you. i promise there are so many respectful, nice, talented photographers out there."
Pretty Little Liars star Shay Mitchell was among the other celebs who slammed Marcus' predatory behaviour.
In an IG story, she posted that she was "disgusted" by Marcus' behaviour and that the social media platform "has become a playground for predators."
She also issued a warning for her followers: "If someone is treating you with disrespect, acting inappropriately or trying to leverage their 'status,' speak out."
Marcus has since deleted his Instagram account and is yet to comment on the situation.
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