Troll fags:
Sonograms have caught fetuses, male and female, masturbating in the womb (albeit with no climax.)
Some people, particularly girls, report masturbating as one of their earliest memories, even in diapers.
Climaxing starts showing up around five or six. (Although without ejaculation in boys.) I was a late bloomer at eight or nine, and didn't start getting messy until 12 or 13. (male)
Girls can accept a (carefully introduced, well lubricated) penis starting around seven. Before that, severe vaginal damage may result.
Many cultures, including traditional Western Europe and early American culture, have had girls marrying off as early as nine or ten.
This idea that any sex at all before sixteen or so is a horrendous violation worse than death is ludicrous, and probably does as much damage as it prevents.
Not that a big age difference isn't ripe with opportunities for actual abuse, no. It's just been blown way out of proportion as being a near universal biological fact for the purpose of turning large numbers of people into hardened criminals who can be tracked and controlled.