(Bold by me)
I know a guy who thought he was dating a 21-year-old. I think he was late 20's at the time. The girl's mother was aware they were dating and that he was over 21. He was even helping the mother catch up on some bills.
He decided to end the relationship, and surprise surprise! The mother gets ticked that he will no longer be helping her out, so she informs him the girl is only 15 and she is going to press charges against him.
His court-appointed attorney told him to take the plea agreement offered, because it was his word against the mother and the girl (who had suddenly changed the whole scenario...supposedly he knew the girl's age, the mother did not know they were dating, the guy was the mother's friend, etc.) He took the deal, and now he's forever branded an SO, although he had no clue he was doing anything wrong, nor did he have a clue what accepting that deal would entail.