The story is more or less a loose commentary on capitalism, tackling loneliness, cyclical generational jadedness/rosy-retrospection, having meaning in life, and coping with a loss of said meaning - providing a look into the "real" inner workings of the manga/entertainment industry.
Overall, the protagonist just fills the aching void in his soul with "the pleasures of the flesh" for like half the narrative. Most of the other characters are just concerned about preserving their professions - as you'd expect of any self-loving professional or anybody for that matter.
I think there's very little payoff for reading it beyond becoming needlessly depressed with the "realism."
