Who is Sir Francis Hinsley from The Loved One and what is their importance?

Sir Francis Hinsley works in the public relations department at Megalopolitan Pictures, although he once was the chief screenwriter there. An old man when the novel begins, his former fame has faded to nothing and his house in the Hollywood hills is in disrepair. He is having a hard time at work, and when he fails to create an interesting "back story" for one of the starlets, he is summarily fired.