Did I tell you I have a crush on a close friend?
Cool. What attracts you to her?
Because she's easy to talk to about sex without being judgmental.
Crushes can happen sometimes but you have to consider whether you would want to risk your friendship to seek a relationship. The relationship might not end well and you will lose a good friend.
My motto: nothing ventured, nothing gained.
Just be aware that it comes with a risk. If things don't work out, it's unlikely you'll be able able to return to things as they were.