This manga was great. I managed to finish it all in under 24 hours, and had fun reading it. However, when I got to the end I didn't really feel satisfied with finishing it. There aren't many arcs and the story is really fast paced. Once one arc ends, immediately another one will begin right away, which I really loved. The situations the protagonists got themselves in sometimes seemed too dangerous to survive, but its fiction so what the hell. The quality declined near the end and the zombie infection plot sort of grew into something weird. The characters were nice and enjoyable since they weren't all boy scouts. More importantly, there were almost no female characters to ruin the story. There are like 2, and fortunately both of them are written well. They weren't moe nor were they the forced "strong badass" type; they were both normal. All in all, I don't regret reading this, but I didn't feel too invested in it. Lets just say I had fun, but don't think I'll ever be rereading it.