The legal age (and I’m speaking from Australia so don’t go off at me about ages) here is 16 for females and 18 for males. They are your LEGAL ages. If that is your LEGAL age, than that makes any other age younger than those ages illegal (for example. If the female is younger than 16, it’s illegal. If they guy is younger than 18, it’s illegal. If the 16yr old female is having sex with a person younger than 18, it’s called as illegal. If an 18yr old is having sex with a female younger than 16, it’s illegal and rather disgusting). Why would they say ‘Sex is legal at this age.. oh but wait if you are both under the ages than it isn’t illegal! That would be silly’
If a 16yr old is having sex with someone in excess of say 19, that’s a little extreme and parents can play the ‘she was forced’ line if they find out and take it to police. Underage sex is hardly ever policed and there are hundreds of thousands of people out there having sex at underage/illegal ages and nothing gets done unless parents step in and act on it or the girl or boy cries rape.
Whatever age is your legal law age in your state or country, is the age you are ‘allowed’ to have sex. But like I said, it’s too hard to police so I wouldn’t worry about it.. Well I would but chances of police chatting you out is limited to none, if it’s not done in the most public of places
And it depends with the molestation thing. Depending on age and form it can often be classed as rape, sexual assult and sexual abuse. It’s the same thing but in the court of law they see all things differently to a discreet manner.