is this weird?

Is it weird if my boyfriend told me that the thought of me masturbating is seriously hot, and that he thinks about me when he masturbates? I'm ok with it and it doesn't bother me but when I told my best friend she said that's nasty. Her exact words were, "ew doesn't that gross you out? Masturbating is a private thing he shouldn't think about you doing that or tell you about it"