A few days ago an american added me, and today we were online at the same time.
Chat between me and him:

Never tell your password to anyone.
ESq # Goodman s>bp: hey!
A$AP NIGERIANCUNT: yo
ESq # Goodman s>bp: How can i help you?
A$AP NIGERIANCUNT: l'homme
ESq # Goodman s>bp: Ah, okay
A$AP NIGERIANCUNT: what do u want
ESq # Goodman s>bp: I priced it at 6 keys
A$AP NIGERIANCUNT: what?
ESq # Goodman s>bp: it was the 38th ever crafted
A$AP NIGERIANCUNT: k
ESq # Goodman s>bp: did you notice the craft number?
A$AP NIGERIANCUNT: i added for something else i think
ESq # Goodman s>bp: ok
ESq # Goodman s>bp: are you selling your trading cards?
A$AP NIGERIANCUNT: nah
A$AP NIGERIANCUNT: omg ur poor
A$AP NIGERIANCUNT: ha
ESq # Goodman s>bp: Lol, I am not poor
A$AP NIGERIANCUNT: yes u r
ESq # Goodman s>bp: and even if i was, what do you mean by that?
ESq # Goodman s>bp: What do you mean by "omg ur poor"
A$AP NIGERIANCUNT: ur a ♥♥♥♥♥♥
A$AP NIGERIANCUNT: kill ur self
A$AP NIGERIANCUNT is now Offline.

This level of nastiness is in violation of the TF2OP rules, and this user should not be left to insult people like this.
Screenshot of chat: http://i.imgur.com/ZoG5wQH.png?1

I'm not sure if this is exactly the right way to report this, so if it's not, sorry.