At first, feeling Booth's strong arms wrapped so gently around you was always a surprise and always more than a little off-putting. After all, he was not someone you understood and you were certain you never would.
You don't understand most people. They are overly-complicated organisms, really just vessels of contradictions, and their reasoning never makes any sense to you.
Regardless, you shortly begin to truly enjoy Booth's hugs. Ache for them, even, in a way you haven't ached since you were thirteen.
(Thirteen. Thirteen was complicated, just like people. You remember lying on the roof of a car, gazing at the stars with Russ. You also remember waking up with no parents and no notion that it wasn't your fault.)
You were not always like this. You were not all logic and cold and unfeeling. At the core, you think there might be a part of you that stills resists the logic.
You think you probably used to be a bit like Booth when you were a girl: understanding, emotional, and even empathetic. But that part of you is buried deep down, now, destroyed by the all-too-simple abandonment by everyone who meant anything to you and the foster homes that knew nothing of love.
(You lost. You lost everything. So you shed that skin and became something new, didn't you?)
When Booth's arms wrap about your body, you are transported back to a time before the desertion—when life was simple and you thought it was all right to believe in things like magic and Santa Claus. You were whole then. And when Booth's arms wrap around you, you can feel an undeniable something resound in your chest that cannot be defined by science:
Someone cares about me.
It is, in every way, more truthful than any result a forensic test will ever give you.
And it isn't just Booth: it is Hodgins' respect and Zack's devotion and Angela's fierce loyalty and, later, even Cam's understanding and Sweets' desperation to call you "Bones."
These people—these brilliant people—care about you, and you, who has yet to understand why people do what they do, are helpless to do anything but love them and protect them.
Even you are not immune to the acute (wonderful) pang in the chest when they all gather around you, smiling at you like you are the highlight of the day.
You are cannot resist their love, and you find, with some secret satisfaction, that you couldn't mind if you tried.