The story is about a group of teenagers that get involved in a real life online game called "Rabbit Doubt" where one by one, the wolf kills off a rabbit. They must find out who the wolf is before everyone is killed.
The game is mainly based on, well.. doubt. It becomes difficult for the players to trust each other and always seem unsure about who the wolf is. As the reader, it will keep you guessing on who the killer is until the end.
Most of the characters are not developed enough that it seems like you've seen them before. (ie. the smart guy, the jock, the wimp, etc.) When they die, it isn't as dramatic as it would be if you knew them very well. Despite that, every character has an important role to the story.
While this manga may sound like a kill-a-thon, it is full of psychology and logic. If you are the type who likes to think and guess along with the characters, this is the manga for you. This manga is entertaining but is not for the faint of heart.