Sabi Sabi no Mi

The Sabi Sabi no Mi is a Paramecia type Devil Fruit that allows the user to cause metallic items to rust and come apart. "Sabi" means rust. In the Viz Manga, it is called the Rust-Rust Fruit. It was eaten by Shuu.

Strengths and Weaknesses
The major strength of the fruit, so far seen, is that the user is able to rust and pull apart metallic weapons such as swords. Doing so apparently gives the user somewhat of an advantage against sword wielding opponents.

In the anime, it has been shown the powers of the fruit give the user a permanent defense against swords and other metal weapons. A sword simply touching the user's body will immediately rust and come apart before a cut can be made. It has also been shown in the anime that powers of the fruit can also rust human flesh, probably the iron from the blood.

However, its powers won't protect the user from non-metallic objects, like pachinko shots. Furthermore, if used on a living thing, the rusting effect seems to be reversible for as long as it does not entirely oxidize the entity in question, since Zoro was seen reverting quickly back to normal after his grip of Shuu on him was thrown off by Usopp's projectile. Apart from that, the fruit so far doesn't seem to have any specific weaknesses outside the standard Devil Fruit weaknesses.

Usage
The fruit's bestowed powers, as used by Shuu, have so far been used for both defensive and offensive purposes. Shuu has used the powers of the fruit to rust the Yubashiri of Zoro after catching it in his bare hands. He was then able to pull apart the sword as if the sword was nothing.

Anime and Manga Differences
In the anime, Shuu was able to use the powers to unconsciously defend against one of Zoro's attacks. At another point in the anime, Shuu was also able to use the powers as an attack on living targets. By touching Zoro's arm, Shuu was able to rust Zoro's own flesh. Fortunately, Shuu was knocked out by one of Usopp's attacks before Zoro's body could become completely covered in rust. After being separated from Shuu, Zoro's body was able to return to normal.