I have never been a decision maker, or at least I don’t think I’ve been.
This joke is a bit odd-placed. You're setting the tone for a horror story and this is the wrong humour for horror.
You then follow up to tell us of how many different subjects failed to hold the narrator's interest. He seems stuck-up and unlikeable (and I'm not seeing much of the 'enterprising' – he seems to want for ideas).
To my surprise, my great-uncle had left dozens of papers in there as well, and underneath them, a key.
You need to work on the rhythm of your sentences. I just tried reading it all aloud up until this sentence – your narrator has a tendency to ramble about boring things. Also, I personally advice against using two commas for different purposes in the same sentence. (The first and the third comma in the quoted bit denote different pauses in speech than the second one does.)
my family’s manor in Massachusetts, just a mile outside of Boston.
Heh, you make it sound like Massachusetts is just outside of Boston.
Understandably, the whole matter greatly concerned me, leaving me sleepless for two straight nights.
Really? The guy who's bored of the paranormal is greatly concerned about … people dying with some foreshadowing next to them? At this point in the story I was expecting him to bore of the papers and start taking up origami.
on the twenty sixth
Should be "on the 26th" or possibly
"on the twenty-sixth", unless I'm missing some old way of writing dates.
232 words of foreplay for opening a damn box
You do not, in my opinion, have enough substance to the story to spend a great deal of words describing a scene. I am at this point not at all interested in what is in the box.
The emotions that pummeled my sensitive, gentlemanly demeanor were cruel and uncaring toward it. I was subjected to horror, fascination, and horror all over again. I was subjected to what my anthropology professor in university called an adrenaline rush, during one of his saucier—yet nonetheless edifying lesson—he posited that more than sixty percent of human population was conceived during at least one partner’s rush—and at that moment I knew why old Mr. Taffet correlated the feeling with sex.
Don't know what the first sentence quite means, except that you're definitely playing up the idea that those 232 words were actually
foreplay. I think there's some misplaced punctuation at "one of his saucier—yet nonetheless edifying lesson—". (And of course something that pummels another thing is going to be uncaring or cruel. Really. The gang of grandmas that beat me up wanted to see me hurt. The guy that bought sex from me was a solicitor. Etc.)
You then proceed to tell of the horrifying stench that is beyond words. Of all the times to invoke the Lovecraft cliché, that time was a bit silly.
Your narrator then talks of the alcohol in San Fransisco, and I doubt the alcohol there actually serves every damaged soul form there to Monterey, as there is a prohibition going on at this time. I am rather certain people were a tiny bit more clandestine with their booze than you describe. One website tells me that the speakeasies in San Fransisco were mostly rectangular rooms with curtains, and if there was an unexpected raid they would reopen the next day with new street numbers and different-coloured curtains. This implies at least some discretion. I don't think they emitted that many cries of excitement audible to your narrator, is all.
Having no idea how this woman in San Francisco obtained a key just like my great-uncle’s—or, conversely, how my great-uncle obtained a key like that of this woman in San Francisco—intrigued me greatly, perhaps most greatly.
This sentence is awesome, though. It's the 'conversely' and the part that follows it that does it.
I really like the part about the moon not being protective - it strikes a chord somewhere inside of me, as I often think of the moon as a protector.
I don't think it's ever explained or even alluded to in the story, why on earth the 2-hour deep staircase exists at the floor of the boiler. That part confused me.
In a way I never left that cavern under Boston, because my thoughts never could.
This is a good line, too.
All in all, not a very original story, and one that could be improved greatly. You have a good grasp of words – sometimes. Try to nurture that. Maybe next time, try to write a new(ish) take on the old classic Lovecraft story. How difficult it is to adjust to a regular life when driven insane by things that actually drive one insane. (Not just giant non-Euclidean beast; try something new.) Or maybe something completely different.