As for mental maturity...what makes 16 or 18 a good age? I knew 16 year old girls having sex with guys in college and they were responsible and controlled. I know 24 year old women and men who STILL can't handle sex.
Like anything else, you're as prepared as your parents make you. If your parents act like it doesn't exist then you're going to have to learn on your own which is the bigger problem.
And yes, I hate Bronies and all the other stupid internet crap that lets grown men act like little girls. It's disgusting.
--
Realo won gold at the Sex Olympics with a BROKEN FRIGGIN NECK.-Voltch