None in this situation, since there was no fraud perpetrated (financial) or infliction of severe distress.
What you are describing is carried out by dozens if not hundreds of YHR users every day and millions of people on social media networks and dating sites. It's commonly called catfishing.
Your best defense is to continue to be cautious about whom you reveal yourself to and make sure you have a comprehensive method of ensuring the identities of the people you talk to.
You have no legal defense and for that matter it's not strictly against the terms of the site (if distasteful) so your report will probably have a negligible effect.