I sometimes will look at a 15 year old femal and thing "God damn look at that." But it stops there because she's a child. They just cant stop.
That's where it gets a bit sticky and diverges from actual biology into dogma and societies made up rules which are subject to change.
That's when you do what is the current rules in society in order to not get in trouble, since trouble isn't worth it.
15 isn't a child in the same way that you could call a 10 year old a child.
There are plenty of 15 year olds and up that are running around this country right now, robbing, raping, carjacking and murdering folks.
15 is plenty old enough to be starting a family and reproducing and that was very common until recently in America.
It's actually still legal in many states in America, you just have to go to court and get a judge to sign off.
In other countries around the world 15 to 16 is considered an adult for all matters sexually.
Here apparently, we have fixated on the number 18 so that's what everybody is all up in arms about, despite actually sometimes 17 being the legal age in some states and such. Interestingly enough the more controlling ones in our society thought 18 wasn't enough for other things they didn't like so they decided sure you are an adult, but you still can't go buy alcohol or a handgun for self defense until we get a higher arbitrary number like 21.
Since current society in America is all messed up about sex and such, it's always a good idea to stay clearly well over the arbitrary 18 line despite there being legal exceptions, because you never know when some angry young crazy woman will be trying to destroy you because you didn't make her the princess she wanted to be.
I personally (as much as some folks will freak out at the idea) think that 16 and 17 year olds who fully knew what they were doing and were willing participants and even instigators in sexual activity, trying to claim that they are "child abuse" victims, does a significant disservice to real actual children who were children and actually got forcibly raped and abused.
That being said, any decent men who are older and intelligent and wise, probably will steer well clear of even 18 year olds as it's not worth the drama, and probably will be looking at women who are a fair bit older and have less crazy.