Do you know anything about Sumo? Do you like Sumo? Neither do I. But that doesn't stop this manga from being any less enjoyable to read. The story isn't groundbreaking. It's your standard sports shounen plot, but it's done well. It progresses at a nice pace and keeps it interesting. The characters are where Hinomaru-Zumou really shines. Especially the protagonist. Multidimensional, well-written, likable/interesting, understandable backstory... It's all there, and then some. If you're looking for a fun new manga to pick up, Hinomaru-Zumou is a pretty good choice.