That, or his mind is blocking some serious parental abuse.
Also, both characters are miserable. Calvin has no friends, so he creates one to make his life more bearable. A friend who, incidentally, is nothing like him: Calvin is an impulsive, whiny, shouting ... child, really. Hobbes, meanwhile, is a cool and collected philosopher. Likewise, the narrator hates his life -- it's little wonder why he might sink back into his old hallucinatory habit and resurrect Hobbes, albeit an R-rated version named Tyler. A version who, as we've seen, is a cool, collected philosopher who fucks junkies like a machine.
It's nice to see that they still share the same activities.
And it's not like Calvin and Hobbes don't have experience in running a secretive males-only organization before. G.R.O.S.S, or Get Rid Of Slimy girlS, a club that the duo operated for most of the comic's lifespan, is a predecessor to the titular terrorist organization, Fight Club. Everything's got to start somewhere, right?