That’s why I said “MAY include. . . two 15 year olds.” Typical legalese waffling, I know, but it depends on your state. Although I haven’t researched the issue recently, I do know that a decade ago, a few states did include intercourse between two minors of similar age in their “statutory rape” statute. At that time, a few states only prohibited males from such conduct, in what I believe to be not only unconstitutional, but also unrealistic provisions. The concept of prohibiting intercourse between similarly aged minors is it is not what you describe as taking advantage of another’s inexperience which the legislature is seeking to prohibit, but rather any sexual conduct with any minor, regardless of the age of the other partner. Although this may seem unfair, labeling it unfair includes the assumption, which many would oppose, that it is OK for minors to have sex with someone of similar “experience.” If you look at it as a purely legal concept, and put aside moral prohibitions, if a minor is legally incapable of consenting to sexual conduct, the age of the partner is irrelevant.
I do recall being in paternity court about a year ago and a 22 year old woman had brought a paternity action seeking child support. The defendant, representing himself, argued he could not be required to pay child support, as he could not work because he was required to attend high school. The judge asked him his age, he was 15. The judge asked the woman if she had filed a rape charge with the police, she said she had not, that the act was consensual. The judge told her that was not possible, as the father of the child could not legally agree to have sex, and had the bailiff take her into custody, and she was charged with statutory rape.