The story is solid. There are no extra characters meaning there isn't anyone in the story that doesn't give you some kind of information to help you make a decision. Because it is a manga there are clues in the panels that the reader may not pay attention to. I dare say, 99% of the readers ignored it. I had the question in my head and moved right passed it just as the writer probably intended. Personally I think the story is woven extremely well, especially given the length. Almost everything you need to figure it out completely is right there. Actually, I almost had it. I had the murderer from the start, but not the why. That little tidbit remained a mystery until the end. Sherlock's usual. Basically, the writer took a Christie mystery and had Sherlock Holmes solve it. Hercule Poirot was busy.
Reading it took no time. It was like binging an anime or reading a book you can't put down. If you're a mystery fan, especially of the old guard mysteries of the early to mid 1900s and/or the subsequent b&w movies that were made based on them, I think you'll enjoy Decagon House.
