Knocked Up star Seth didn't hold back this week when asked to explain his dislike of Justin, 20, saying he actually 'hated' the star.
Seth told The Howard Stern Show: "He's a good example of someone you meet, who you think you're going to hate, and then you get to hate him as much as you thought. You meet him, and he lives up to every one of your expectations of how you hope he will be."
He claimed he was asked if he'd like to meet Justin years ago when they were both at the same German talk show, but when he approached the singer, Justin was acting as if Seth had asked to meet him.
"I was like, 'What the f**k? I don't want to meet you. Don't act all nonplussed to meet me. I didn't want to meet you. I was totally cool not meeting you… But I was like, fine, I wouldn't have said anything, I was like, 'He's a bit of a motherf**ker.'"
He also claimed Justin acting nonplussed to meet him when they bumped into each other a second time. And in January 2014, the actor tweeted following Justin's arrest in Miami on suspicion of driving under the influence, without a valid license and resisting arrest without violence.
His message, 'All jokes aside, Justin Bieber is a piece of s**t', was retweeted a mammoth 200,000 times.
After all that, you'd be forgiven for thinking Justin wanted to let loose at Seth with some choice words of his own but he's surprised us by remaining pretty calm – and gracious.
Justin tweeted: "Seth Rogan sorry I didnt bow down when I asked 2 meet u was probably a bit shy and didn't want to be over the top but still. love ur movies (sic)."
Seth Rogan sorry I didnt bow down when I asked 2 meet u was probably a bit shy and didn't want to be over the top but still. love ur movies.— Justin Bieber (@justinbieber) May 8, 2014
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