Rob Kardashian and Kim Kardashian attend the World's Most Beautiful magazine launch in 2011. Credit: Jason LaVeris/FilmMagic

Not funny! Kim Kardashian explained to a fan on Twitter on Sunday, January 24, that her brother, Rob Kardashian, called her “the bitch from Gone Girllast year because he thought it was funny and was mad at her.

During Sunday’s episode of Keeping Up With the Kardashians, Kim, 35, brought up the since-deleted Instagram post from March, which compared her to Rosamund Pike’s psychotic and murderous character. "This is my sister kim , the bitch from Gone Girl,,,” Rob, 28, had captioned the snap of the bloody Oscar-nominated actress from the film.

"You get purple hair and I get the girl from Gone Girl!" Kim told Khloé Kardashian during the episode, referring to another one of their younger brother’s Instagrams.

"LOL! We still need an explanation for that bc I don't see any comparisons!" a fan by the user name ZOHALxo later tweeted at the reality star. "@ZOHALxo he thinks he's being funny," Kim tweeted back. "I got mad at him and he posted that to get me back."

As previously reported by Us Weekly, Rob — who has gained more than 100 pounds over the past three years and was diagnosed with type 2 diabetes earlier this month — felt like Kim wasn’t being supportive at the time. 

“Rob is in a dark place,” an insider told Us of his odd March 2015 post, while another source added that Rob felt like Kim was being two-faced. “His post was about how she seems caring in public,” the insider explained. “But he feels ignored.”

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