ive been reading this book called Within Without by Jeff Noon and so far the protagonist has ended up with fictional character gregor samsa inhabiting his brain and sending him messages. it kind of rules
basically this detective (of course its detective fiction) goes to a nightmare hell city called Delirium where there are borders everywhere in order to hunt down a movie star's magical glamour/image that has become unmoored from his body and along the way he's dealing with this fucked up city and all its weird inhabitants. i like it a lot