You can get a general sense of Heyuri's culture off this video: https://www.youtube.com/watch?v=CGID6_2D9Q0
And even that is missing some stuff like the albums or the stuff around Kuuchuu Buranko (understandable, since it was made before we watched it). Just because not every thread is full of memes and long-running inside jokes doesn't mean the culture isn't there.