The title is a bit of a tongue twister, but it does sound scary, probably because it has the words "dies" and "drear" in it. Sounds like it's a house of dreary deaths, doesn't it? Well don't you worry, Dies Drear is just a person's name. He was the house's original owner.
Drear was a white abolitionist (person who worked to end slavery) who dedicated his life to helping slaves escape from their masters to freedom. His house was not a place of dreary death, but a place of hope. It was a place where escaping slaves could rest and hide as they made their way to Canada, where slavery was illegal.
So, you might be wondering, what kind of a super-grim name is Dies Drear? Well, even though the story is set in Ohio, Drear was originally from New England. New Englanders in Drear's time (probably the early 1800s to the 1860s) were known for their onerous, heavy sounding names, at least in books. Think Roger Chillingworth and Arthur Dimmesdale from Nathaniel Hawthorne's The Scarlett Letter (1850), set in New England.
Hamilton probably chose the name Dies Drear partly because it would make the title scary and mysterious to readers. Like Thomas, we imagine that a house called "the house of Dies Drear" must be haunted. That makes us want to read all about it. Is the house really haunted? That's up for debate. But, we do know one thing for sure: at least one dreary death did occur in the house – the brutal and mysterious murder of Dies Drear himself.