I used to fap to my best friend's pictures
Why would you fap to your best friend's pictures?
I didn't want to. But I couldn't resist his amazing looks.
It's okay to masterbate, but doing so to your friends pictures may cause things to become complicated between you and your friend. If you find them sexually attractive, you may end up crossing a line if they aren't interested you in a romantic way. You should be honest with your feelings.
It's cool now since he understands. I'm over it now, so there is no need to talk about it.
With the human body we are all faced with urges and desires. It is okay to masturbate in life. You shouldn't do those kinds of things with your friends pictures though because you don't want to make them uncomfortable.