First we need to clear this up. Rape is by definition sexual assault. If there is no sexual assault, the issue is not rape, it remains at the stage of attempted assault. If there is sexual assault, it is rape. This is rape by definition. sexual assault is a type of physical assault, otherwise unacceptable. Therefore, rape is physical assault and the victim is physically harmed. To say that there is no physical harm, or in some cases no physical harm, does mean lack of understanding what the word or act of rape means. or to get it that way requires to be a POS like jackblack.
Rape is a specific form of unlawful sexual assault. It involves violating another person's body through the act of penetration, without their consent. You can argue there is psychological harm and often physical harm to the victim.
This is why you sometimes see idiotic sovereign citizens arguing with police on thr side of the road who just want to do a breath test, that the act of the police officer sticking the breath straw in their mouth to blow into the instrument, is tantamount to rape, because they are doing so, under coercion from an authority figure, and do not consent.
Laws differ from country to country and even from state to state. But an unlawful sexual assault usually includes someone touching another to their genital area, or buttocks, or breasts, without their consent. It's an unlawful assault to a sexual part of the body, for sexual gratification of the perpetrator. But, that isn't a rape.
However, of course, statutory rape doesn't require there to be no consent. Statutory rape cases can involve consensual sex. The only time no action is taken in statutory rape cases where the sex is consensual, is when both involved are underage and about the same age. Because you have to either charge them both, or not charge them both.
If an adult does a sexual act with a person underage, there is generally no statute barring period for Police to investigate it. This means the victim can make a complaint of rape anytime after the event for as long as they live, and the perpetrator is forced to spend the rest of their life looking over their shoulder. Historical rape cases which are reported rape cases after many years have past, tend to destroy lots of people's lives. But it can bring justice for the victim and punishment for the perpetrator.