If I am 18, and my girlfriend/boyriend is only 16 is it a crime for us to have sex?

ARS §13-1405 says that it is illegal for someone to have sexual conduct with a person who is under 18. Under that law a person who does have sexual conduct with a minor may be liable for prosecution, even if the act is consensual. But, under A.R.S. 13-1407(F) it is a defense to that statute " if the victim is fifteen, sixteen or seventeen years of age, the defendant is under nineteen years of age or attending high school and is no more than twenty-four months older than the victim and the conduct is consensual."