Yomi Yomi no Mi

The Yomi Yomi no Mi, also known as the Yomi Yomi Fruit, is a Paramecia type Devil Fruit, which allows the user to come back to life after being kllled. Initially, this Devil Fruit has no effect except for the usual side-effects such as not being able to swim. When the user dies, however, it brings them back to life once. Upon death the spirit is haulted from traveling to the realms of the dead and is instead allowed to locate its body and be revived. However, this does not prevent the users body from decaying, hence Brook's skeleton appearance. The term, "yomi", could have one of two meanings, and both are implied in Brook's explanation of the fruit. It could be short for "yomigaeru" (蘇る, "revive" or "reborn"), or it could come from "yomi no kuni" (黄泉の国, "realm of the dead" or "the underworld"). It was eaten by Brook.

Strengths and Weaknesses
The major, if not only, strength of the fruit, as demonstrated by Brook, is that it just gives it's user a second life after being killed. After death, the user continues to exist in whatever state they were revived as and can even go as far as to grant a form of "immortality" that lasts until the user suffers a second death. Though the user gains a second life, their body however will continue being a lifeless corpse and will continue rotting away until the user's soul can find back the body. When the user's soul finds back their body, the powers of the Devil Fruit will however fortunately support the user's well being in the case that their body maybe in a condition unable to support life.

Other than that, the user is mostly affected also by standard Devil Fruit weaknesses.

Usage
While the fruit's only major fruit's bestowed power is only usable after death, it's secondary powers however are rather useful in keeping Brook basically "alive". Through the fruit's powers, Brook is able to function without the presence of necessary and vital body parts that have been decomposed long ago. He is able to move and stand up without the presence of tissue and muscles to support him. He is able to interact with the environment around him without the presence of eye balls or any other sensory organ to aid him. He is even able to digest food and defecate like any other normal living thing. He is also able to expell tears when crying, even though he is void of tear canals.

Due the fruit's powers holding up and moving his light skeletal frame, Brook is able to perform some things unique to him such as jumping up very high and running on water.

Trivia

 * Brook's soul, upon returning to the mortal to search for his body, resembles a hitodama, a representation of the recently deceased commonly found in Japanese folklore and pop culture.