NCIS 〜ネイビー犯罪捜査班 10x02 - Why was Gibbs uncomfortable and told Abby not to get too personal when attempting to help her with her nightmares?

He has never been like that before, he has always helped her unconditionally no matter how personal it got, so that seemed out of place. I respect people that want them as a couple, but I see them もっと見る as father/daughter so does anyone have a non-romantic answer?