I'm guessing he's a big fan of Onomatopoeia (who isn't really!?) and maybe some campy Batman episodes with Adam West.
Found from hereFor more pics & fun art go here D. Billy Interesting side note! He's based in DC!
Hahaha! thats funny! I totally though I recognized the "Ream" graffiti but thought...naaah, and then you said he's based in DC. Go figure.