The Reapers' Game––also called the Game––is a game which those who've died can participate in for a second chance at life. However, there are a lot of things trying to erase (literally meaning kill) you. Chances are you're not gonna survive the week if you don't trust your partner.
In order to be able to participate in the Reapers' Game one must pay an entry fee. The entry fee is something the person values most; it can be virtually anything. There are basically no limits as to what the entry fee can be. In Shiki's case her entry fee was her physical appearance which resulted in her taking on an entirely different appearance. For Neku it was his memories, and for Beat it was his sister's memories of him. If one manages to survive and win the Game they will get their entry fee back. If not they lose it and their right to exist.
In the Game, participants are called Players and can be easily identified by their Player Pins, plus they cannot be scanned. Players must form a pact with another Player in order to complete missions sent out by the week's Game Master. Missions are received on the Player's cellphone, and if there is a time limit a timer will appear on their hand. Not all the Players have to complete the mission in order for the mission to be completed. As long as one person completes it it is completed for everyone. However, it is a good idea not to ignore the missions entirely either as each Player is given a certain amount of points which will determine their score at the end of the week.
Also, the Game takes place in an alternate version of Shibuya created by some person called The Composer. This version of Shibuya is called the Underground (UG), which coexists with the real world, called the Realground (RG). Players can be found within the UG and are normally invisible to those in the RG. However, those in the RG can be seen by those in the UG. If a Player enters a building with a special decal on the side they will become visible in the RG for as long as they are in that building. The Game is also not a weekly event, but rather something that happens every once in a while. It is exceedingly rare to happen multiple weeks in a row.
Another thing too is there are things out to kill the players, such as the Noise and Reapers. However, Noise will not attack Players who have formed a pact. Noise are animal-like creatures with unusual limbs. The picture on the right is an example of one of the many Noise you will find. There are varying difficulties of Noise which can be identified by their symbols when you try scanning. There are also different kinds of noises which can do different things depending on their color. Red are the most common, orange are often found attached to people or objects, gray are Taboo Noise which will chase you as soon as you start scanning and are stronger than normal Noise, and green are special pig noises which can give you nice things if you can kill them before they bounce.
Just like there are different kinds of Noise there are also different kinds of Reapers. All Reapers have the ability to create and destroy Noise at will and some will even use them to attack Players in order to erase them, as they are not allowed to attack Players directly. These Reapers who attack the Players are known as Harriers. There are also some Reapers who don't attack Players at all, instead creating walls and various requirements in order to bring those walls down. These Reapers are known as Supports. All Reapers can be identified by the black wings on their back and can freely move between the UG and the RG. However, when they are in the RG their wings will disappear and they cannot use their powers.
At the end of the week the remaining Players must defeat the Game Master, and if they should survive their points are added up. If a Player scored the highest amount of points he or she will come back to life. If not they can choose to participate again or even join the Reapers. If not you can always face your end with erasure.