Justin Bieber and Barbara Palvin posed for pictures at the Victoria's Secret Fashion Show in New York, Nov. 7, 2012. (Twitter)

Justin Bieber's legions of tween fans are, once again, causing a stir on Twitter by trending "Barbara" after the teen pop sensation hung out with supermodel Barbara Palvin at the Victoria's Secret fashion show.

The supermodel had previously, about 11 months ago, remarked on a video webchat that she was not a fan of Bieber's girlfriend Selena Gomez. However this was to come back and haunt her after the 19-year-old fashion model hung out with Bieber after his performance at the Victoria's Secret fashion show on Wednesday. The pair posed for several photos together and retweeted a number of each other's messages, leading Gomez, for reasons that are not entirely clear, to tweet a picture of a younger Bieber and his friend "L'il  Twist" with Barbara in the background.

This brief Twitter tiff was enough to send millions of teenagers to Twitter to attack or defend some combination of Palvin, Gomez and Bieber. Twitter user Mix, for example, states "Barbara isn't pretty as selena. So, stfu," while Robin is more of a fan, tweeting "Barbara Palvin is famous because of a picture. Selena Gomez is famous because of talent. That's the difference."

Proving that Bieber's fans are hardly a "forget it and move on" type of crowd, "Barbara" is still trending on Friday, November 9.

Elsewhere on Twitter microbloggers are tweeting short pieces of advice using "#ThreeWordAdvice," celebrating the end of the week with "#TGIF" (Thank God Its Friday) and explaining what it is that they will never understand, while Malaysian actor and TV host Fahrin Ahmad is trending in fifth place.

The top 10 most talked about topics on Twitter on November 9 at 2:20 pm GMT are: 

01.  #iWillNeverUnderstand
02.  #NakakamissYun
03.  #CosasQueHagoEnClases
04.  #15FatosSobreMim
05.  Fahrin Ahmad
06.  #ASK2012
07.  Barbara
08.  #CancionesQueSonPerfectas
09.  #ThreeWordAdvice
10.  #TGIF