Hello to my fellow long hair lovers,

I have a question: My Girlfriend has awesome long dark straight hair (maybe i can post a picture someday). She knows that i love it, but not in that fetish way. How do i say that i get hard just because of her hair so that she gives me a hairjob or let me cum in it.

Maybe someone had a comparable situation and can tell me how they told their gfs/wifes about the fetish.