Seth Rogan, Justin Bieber
Rogan: Jason LaVeris/FilmMagic; Bieber: Kevin Winter/Getty Images for Coachella

Justin Bieber is not staying mum while Seth Rogen sullies his good name: after the "Neighbors" star appeared on "The Howard Stern Show" earlier this week to expound upon his hatred for the Biebs, the pop superstar fired back on Twitter, and defended himself before complimenting Rogen's filmography.

"Seth Rogan sorry I didnt bow down when I asked 2 meet u," Bieber wrote on Thursday morning (May 8), "was probably a bit shy and didn't want to be over the top but still. love ur movies."

Inside The Seth Rogen-Justin Bieber Feud

Bieber is toeing the line between lobbing insults back at Rogen and trying to make nice in this tweet. The misspelled name and sarcastic "bow down" phrasing suggests that the Biebs does not want to apologize to the actor, but then again, his admission that he was "probably a bit shy" seems heartfelt. The fact that Bieber loves Rogen's movies may compel the 20-year-old to see the new frat-house comedy "Neighbors" -- if not in theaters, then maybe on DVD, in a few months, when the dust has settled.

"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," Rogen said to Howard Stern. He then detailed his two interactions with Bieber -- first at a German talk show, when Bieber acted nonchalant while meeting him, and then at the 2011 MTV Video Music Awards, where Bieber was fooling around with a pet snake.

Of course, this feud started back in January, after Bieber was arrested on suspicion of DUI. Rogen posted to Twitter, "All jokes aside, Justin Bieber is a piece of shit."