Regarding Holly, the first term that came to mind was brittle, defined in the sense of brittle laugher. When I say shallow, it's not the fluffy headed type of shallow, where there is no knowing any better. It's where you understand greater meanings, yet do not persue them. You attempt of to fill the emptiness with busyness, meaningless doings.
I'm sure "In Cold Blood" is a great read for many people. Delving into difficult, dark subjects is in some ways necessary, for some, for others...
Maybe I'm strange, but I mull & have for as long as I can remember. Writing my response to you brought another murder back into my mind, one that happened around the same time as Capote's book was published. The adults didn't talk about it around children, but you'd catch them talking about it with each other in hushed tones. I grew up in a small town & young women were just not found dead in a pool of their own blood, with over 30 stab wounds, not in small town, middle America. Diane had been a neighbor & my favorite babysitter when I was younger. Her murder has never been solved.
Anyway, I try to be careful about the kinds of things I bring into my psyche to mull about.
Your bonus trivia, LOL Yes, I can see that!
Holly was the type of character you can trace back to Becky Sharp (Thackery's Vanity Fair) etc.
And yeah, Capote was somewhat fascinated by the dark side of life, which he eventually fell into. I'd argue that he more or less squandered his talent, which was sizeable. Too many parties, too many drugs, too many wasted days yakking with rich women.
Bonus Capote Material (Warning: somewhat racey): Capote never went to college. Rather, he took a job in the mail room of The New Yorker Magazine. The story circulates, which he never denied, that one of his jobs was going across the street to a hotel where humorist/cartoonist James Thurber would meet his mistress. Thurber, who was by then almost blind, would have young Truman help him dress for his return to the office. Although Thurber's wife would dress him in the morning and undress him at night, vanity prevented asking his mistress to help. Unhappy with his assignment and ever the moralist, Truman turned the old man's socks inside out, so that his wife would be sure to notice when she helped undress him at night.
One of those stories that is repeated so often that it's almost as good as true.