The phenomenon of Woolwich arsenal fans being completely obsessed with Spurs, constantly talking about them and generally thinking about Tottenham Hotspur all the time. Whilst therest of the world barely knows who the Woolwich even are
See Troopz and DT were taking about Kane on AFTV again, living rent free in their heads. #COYS
An insult commonly used on various 4Chan boards.
It insinuates that the person being insulted lives "rent free" with his or her parents, and thus must be a NEET with no life.
Note that when used, insults like this will often either completely shut down an argument or turn it into a rapid back-and-forth flame war, derailing it.
Anon1: "Wow, that shit was cringe"
Anon 2: "Rent free"