How do I tell her?

I've been reading my friends boyfriends body language and it seems that he isn't interested in her and is just dating her to get a higher popularity ranking but he doesn't seem like a bad person I just have come to the conclusion that his heart belongs to another but I haven't been able to pin-point the person he loves! It's so annoying it makes me think that maybe my conclusion is wrong but usually my conclusions are more than true they are basically super human!  Well that's the end of my constant blabbing about yesterday's life!

                 -SH