A Ukrainian prankster says he tried to kiss Kim Kardashian's bum because he was protesting against her use of "fake butt implants".
Vitalii Sediuk posted online that he wanted to encourage the Kardashian family to promote "natural beauty" to the teenage girls who follow them "blindly".
He has targeted many celebrities including Gigi Hadid and Leonardo DiCaprio.
Some claim his "pranks" are "sleazy".
While in Paris on Wednesday, a man approached Kim Kardashian.
He tried to grab her leg and kiss her bottom, but was quickly stopped by one of her bodyguards.
Soon after, Vitalii Sediuk explained his reasons for the stunt.
The 27-year-old wrote on Instagram: "I was protesting Kim for using fake butt implants.
"I encourage her and the rest of Kardashian clan to popularise natural beauty among teenage girls who follow and defend them blindly.
"I swear I didn't know she was going to be there. So I had to come out with an idea very fast.
"Does it mean if I don't go to celebrities, they come to me? Lol."
This came less than a week after another one of his "pranks" where he grabbed model Gigi Hadid in the street.
She elbowed him in the face and later tweeted: "How dare that idiot thinks he has the right to manhandle a complete stranger?"
Many on social media have accused Vitalii Sediuk of having no "respect for women's bodies" and believe his stunts are a form of assault.
However, he argues he is no different to US presenter Ellen DeGeneres, who often plays pranks on her guests including Selena Gomez and Jake Gyllenhaal.
He wrote on Instagram: "When Ellen DeGeneres scares her star guests on her own show, no one calls it an assault, even though not many celebrities truly like it.
"I just don't see the difference between what Ellen does in a professional studio of Warner Brothers and me on the red-carpets or the streets outside the venue."