In Which SHE'S HIS GIRL *cue fangirl squeal*

Season 1, Episode 8

The Girl in the Fridge

Booth: You know when the regular stuff, when it gets old you need to spice it up or it’s over.  The sex is good you don’t need any help.
Bones: (smiles) Well that’s for sure.
Booth: I’m sorry?
Bones: I was agreeing.
Booth: Yeah, well don’t. Okay. It kind of freaks me out.

It freaks him out. Heeheehee. Oh, I love it. Of course he's not used to thinking of her as a sexual being, since she normally spends all her time with bones, so to have his view of her be changed like that, especially for a guy like Booth... it'll freak him out for a while. A long while.

We interrupt this post to bring you a FANGIRL MOMENT:

Booth: Oh cause the nutty professor has graded your paper.  What’d he give you anyway? I was always happy with a B.Bones: I never got a B and I never will. 
(Booth stops walking and she continues on.)Booth: (to himself) That’s my girl.

OH MY GOSH, “THAT'S MY GIRL”. BE STILL, MY FANGIRLING HEART. TOO CUTE. <3

And of course, it's the further development of his affection for her, which leads to his protectiveness of her, and thus, his white knight syndrome.

And, to end, we have the last line:

Bones: You had something to accomplish and you found a logical way of getting what you needed. I probably would have done the same thing.

Another early-episode reminder of how, deep down, they are more similar than they appear.