This is why Ronda Rousey is not a Belieber.
Anyone who saw Ronda Rousey's last fight (or any of her fights, for that matter) knows that she's the last person on Earth that you'd want to be mad at you, but it seems as if Justin Bieber didn't get the memo.
The MMA fighter and UFC Women's Bantamweight champion, 28, threw a little bit of shade Bieber's way in recalling her meeting with the 21-year-old pop star at the Cannes Film Festival earlier this year.
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"Justin Bieber was actually really rude to my little sister at the Cannes Film Festival," Rousey told Cosmopolitan.com. "My little sister is very hard to impress. She really didn't care about anybody that was at the Cannes Film Festival, but I wanted to spend time with her and Justin Bieber was over there taking some pictures with some ladies and she suddenly got really excited. She's like, 'Do you think he would want to take a picture with me?' I was like, 'Sure, Julia. Don't worry about it!'"
It seems Rousey spoke too soon, as Bieber shut down their interaction in less time than the 14 seconds it took Rousey to defeat Cat Zingano in February.
"I walked over there and said, 'Excuse me,' and he turned to me and goes, 'I've already taken a billion pictures today, okay?'"
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Rousey persisted, trying to explain that her sister was the only 16-year-old girl at a party full of adults.
"I only got a, 'Yeah, but...' out, and he goes, 'A billion,' and walks off and totally snubbed my little sister."
Given how Bieber apparently left the teenager in tears, it doesn't look anyone in the Rousey family is still a Belieber.
"Yeah, I don't think I'd want to hang out with him," Rousey said. "I'm not a Belieber. I was, but I'm not anymore."
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It's a good thing Bieber is friends with undisputed boxing champ Floyd Mayweather, but we're not sure that even that connection could save him from Rousey's wrath. Rousey beat Mayweather out for Best Fighter at the 2015 ESPY Awards.
Rousey will be on ET Monday.