Justin Bieber's Fans: Crazy or Just Babies?

Jan. 5, 2010 — -- Who knew a nuzzle could breed so much nastiness.

After Justin Bieber, 16, was photographed getting cozy in the Caribbean with another teen pop star of the moment, Selena Gomez, 18, his fans quickly turned on her via Twitter, even though neither the singers nor their representatives have labeled the relationship as anything more than platonic.

Some of the more vitriolic tweets:

-- roses are red, violets are blue, @selenagomez if you'll break @justinbieber's heart I'm gonna kill you :3
-- @selenagomez If you are the Girlfriend of Justin I will Kill you I HATE YOU :@ !!!
-- @selenagomez whore cancer whore .. like i'mm kill myself cuz i saw you and Justin kissing well thankyou Selena thankyou now i'm killing myself

Amid the cacophony of criticism, some support surfaced:

-- When I see those piccs from @justinbieber & @selenagomez I'm freaking out inside. But then I realize, he likes her so ... I won't stop him :)
-- @selenagomez I love you with all my heart & I always will, no matter what you do or who you date. I'm just happy to see you happy :) xoxo.

A little love, a lot of hate. In any case, a flood of feelings. This isn't the first time it's happened. Last month, the "Baby" singer's fans flew into a frenzy after he and Gomez were snapped leaving an IHOP restaurant together. (At the time, Gomez told ABCNews.com, "It was just pancakes!")

Last May, after Bieber joked on Twitter that Kim Kardashian was his new girlfriend, his devotees came at her, claws out. It begs the question: Why are Bieber's fans so invested in his personal life?

"That's sort of the history of his fan's behavior. He has an intensely loyal fan base," said People magazine reporter Carlos Greer. "He's had to cancel concerts because they've gotten out of control. Any female pop star, actress, whoever, who sort of intrudes, this is pretty much their reaction. He's the king of the current pop boom. He's not only their pop crush, he's their pop idol."