Just trying to put myself in a 13 year old boy's shoes. For a goof, I'd probably tell the brother really shyly that I find it hard to concentrate on the study.
"Why's that, young man?" Brother Bob will ask.
Then you raise your gaze and stare him dead in the eye. "Because I'm attracted to you, brother Bob."
BAH! If he's of the right mind, he'll drop your study like a hot potato due to the inappropriate nature of things. But that's a dicey bluff to pull in WT land, given the industrial scale of pedophila issues they're having.
Nonetheless, if brother Bob cares about not encouraging your "confused feelings" (there's a whole Young People Ask chapter on the pubescent "phase" of homosexuality), he'll back the hell off.