Like most of his ilk on here, they rarely show their true face on the open forum. It's mostly done by pm or chat, and the worst of what they show in the open tends to get deleted for obvious reasons.
You can still use the search function for his username (punkrotten) and see some of the crap he's said when he tried to come back using other names. Search is in the little yellow-orange bar near the top, towards the right. Click 'show posts'.
This is a good place, but it's still the internet. Users should always be wary, and mods always have to be vigilant. Sometimes banned users even come back using a different computer and thus IP address and the mods have to figure out what's going on like detectives, going by little clues.
That's one of the reasons why it's important that predatory behavior gets reported. They rarely limit themselves to just one potential victim.