Deathnote Rules

The owner of the note can recognize the image and voice of its original owner, i.e. a Shinigami.
The person in possession of the DEATH NOTE is possessed by a Shinigami, its original owner, until they die.
If a human uses the note, a Shinigami usually appears in front of him/her within 39 days after he/she uses the note.
A Shinigami has no obligation to completely explain how to use the note or rules which will apply to the human who owns it.
A Shinigami can extend his life by putting human names on the note, but humans cannot.
A Shinigami cannot be killed even if stabbed in his heart with a knife or shot in the head with gun. However, there are ways to kill a Shinigami, which are not generally known to the Shinigami.
The Shinigami must at least own one DEATH NOTE. That DEATH NOTE must never be lent to or written on by a human.
If the Shinigami decides to use the DEATH NOTE to kill the assassin of an individual he favors, the individual's life will be extended, but the Shinigami will die.
The dead Shinigami will disappear, but the DEATH NOTE will remain. The ownership of this DEATH NOTE is usually carried over to the next Shinigami that touches it, but it is common sense that it is returned to the Great Shinigami.
Only by touching each other's DEATH NOTE can human individuals who own the DEATH NOTE in the human world recognize the appearance or voice of each other's Shinigami.
The Shinigami must not tell humans the names or life spans of individuals he sees. This is to avoid confusion in the human world.
It is prerequisite for the DEATH NOTE used in the human world that a living Shinigami makes sure that the humans in the human world use it.
It is extremely unlikely that a Shinigami who has possessed a human could die, but if he should die, the DEATH NOTE that he brought into the human world will not lose its power.
If an individual with ownership of more than two DEATH NOTES loses possession to one of the DEATH NOTES, he will not be able to recognize that DEATH NOTE's Shinigami's appearance or voice anymore. The Shinigami himself will leave, but all the memory involving that DEATH NOTE will remain as long as he maintains ownership of at least one other DEATH NOTE.
The Shinigami must not stay in the human world without a particular reason. Conditions to stay in the human world are as follows:
1. When the Shinigami's DEATH NOTE is handed to a human. 2. Essentially, finding a human to pass on the DEATH NOTE should be done from the world of the Shinigami, but if it is within 82 hours this may also be done in the human world. 3. When a Shinigami stalks an individual with an intention to kill them, as long as it is within 82 hours of haunting them, the Shinigami may stay in the human world.

The Shinigami must not hand the DEATH NOTE directly to a child under 6 years of age (based on the human calendar).
If a person loses possession of a DEATH NOTE, they will not recognize the Shinigami by sight or voice any more. If however, the owner lets someone else touch his DEATH NOTE, from that time on, that person will recognize the Shinigami.
The owner of the DEATH NOTE cannot be killed by a Shinigami who is living in the world of the Shinigami.
Also, a Shinigami who comes to the human world, in the objective to kill the owner of the DEATH NOTE, will not be able to do so.
Only a Shinigami that has passed on their DEATH NOTE to a human is able to kill the owner of the DEATH NOTE.
There are male and female Shinigami, but it is neither permitted, nor possible for them to have sexual relations with humans. The Shinigami also cannot have sex with each other.