About Gomu Gomu no Mi
The Gomu Gomu no Mi is a Paramecia-type Devil Fruit that grants the user's body the properties of rubber, effectively making them a Rubber Human (ゴム人間, Gomu Ningen?, English: "Rubber Man/Person"). Originally, the fruit was called Hito Hito no Mi, Model: Nika and classified as a Mythical Zoan-type fruit that allows one to transform into the legendary "Sun God" Nika (and gain his rubbery attributes), before being renamed and reclassified by the World Government to hide the truth. In the present, only a few are aware of the fruit's true nature, and its existence was never known to be recorded anywhere.
Around 900 years ago, the fruit was eaten by a mysterious figure known as Joy Boy, the first ever pirate in history. 13 years ago, the World Government had managed to capture and secure the fruit after chasing it for over 800 years. However, during transport, it was stolen by Shanks and his crew. Shortly after, it was heedlessly eaten by the series' protagonist, Monkey D. Luffy.
The Gomu Gomu no Mi is a violet, spherical shaped fruit, similar to a cantaloupe, with a stem sprouting out of the top, with swirls that go in a curly "S" like-pattern. Its overall appearance greatly resembles a Yubari King.