Sexual offender can be almost nothing.. Friend of mine managed to get himself on the sex offenders register.
When he was 20, he met a pretty gal at a nightclub.. She latched on to him, and they ended up going out.. After a while, she started staying over at his place at weekends, and things were good.. She looked young and fresh faced, so always got ID'd, but always pulled out her ID and all was good..
Then eventually he got to meet her folks, and over dinner he said approximately that he knew where she got the cooking skills from now, because she made fantastic breakfasts for him when she stopped over.
That's when conversation pretty much stopped.. He got worried about having made a social faut pas, and left pretty early.
Next day, the police came round to his place and arrested him for rape. Turns out the gal was 15, with false id (age of consent is 16 in UK), and her nights out she was saying she was spending at friends houses studying.
When the court case came around, he was told that ignorance of her age was no defence, and the fact she'd been lying to him and telling him she was 18 and working was no defence.
End result, he did time, and was put on the sex offenders register. He's a nice chap, and thoroughly decent.. Not the sharpest, but damn honourable..
And thoroughly screwed because a gal lied to him. She had no consequence apart from her folks scolding her for lying about being at her friends' houses.