Why is it that some people just go totally brain dead when any crime involving sexual events happen?  No one is allowed to freely assault another person, regardless if sex is involved or not.  Assault is forcing yourself on another who does not desire it.  That is a crime for Law Enforcement, not an educational establishment, church, business or any other private group.  

If it is reported, and no one will know about it if it is not, then law enforcement needs to become involved according to the law.