What is "Boo Radley Van Cullen"?

[Kyra]

In Pretty Little Liars many people have taken to calling Toby, I think, Boo Radley Van Cullen, mostly as a hashtag on twitter. I have heard its a mixture of other references but I was wondering if someone could explain to me what exactly "Boo Radley Van Cullen" is and why they call whoever it is that? and if I am wrong about it being Toby then who it is? Thanks so much! I just wanted to get some more info before I jump onto this bandwagon. (which i may or may not have done already (: )

[xXVampireWalkerXx]

Well, Boo Radley is a character in the book "To Kill A Mockingbird". And I don't know what Van is supposed to mean, but are they saying Cullen, because it's the last name of the family in Twilight? I honestly have no idea, lol. I'm just giving out my theories.