Kill Your Friends by John Niven is sometimes compared unfavourably in reviews to American Psycho (probably due to the ruthless, callous, murderous businessman main character Stelfox, a record label A&R man) but i prefer it, mainly because it’s very funny. it also has a spinoff, The Second Coming, in which Jesus enters and wins a pop idol type competition run by Stelfox and uses the winnings to set up a Waco style commune, and a sequel, Kill 'Em All, where Stelfox, after becoming an established Simon Cowell type mogul, gets up to further grotty business.
But if you want severely wtf material, The Bighead by Edward Lee will satisfy
it is, if you try them i hope you enjoy