Chōmei

, better known as the is a tailed beast sealed within Fū from Takigakure. It has been captured, extracted, and sealed by Akatsuki. In the anime, the Seven-Tails is indicated to have been one of the two tailed beasts that Akatsuki captured before the start of Part II. It was later resealed into a revived Fū during the Fourth Shinobi World War.

Background
According to Tobi, the Seven-Tails first came into being in the waning days of the Sage of the Six Paths' life; to prevent the Ten-Tails' resurgence, the Sage split up its chakra and used his ability to create nine separate, monstrous constructs of living chakra, which would become known as the tailed beasts. Some time after being created, the Sage of the Six Paths sat down with all the tailed beasts and told them that they would always be together even when separated and that one day they would become one entity again with different names as well as forms than they did then when the time came for them to understand what true power was. The Seven-Tails eventually fell into the possession of Takigakure and was sealed into Fū, but was captured and extracted by Akatsuki.

Appearance
The Seven-Tails resembles a blue, armoured kabutomushi, with six of its seven tails resembling green insect wings, along with the seventh tail, all growing from the end of its abdomen. The stem of the tail is green but the wings are orange. Its eyes seem to be covered by a knight helmet like skull, from inside the "helmet" an orange glow can be seen. It also has spike protrusions on its shoulders and a row of slits on each shoulder, and six legs, three on each side. The legs are also covered by the blue armor, however the last segment on each leg is not covered and therefor green.

Abilities
Not much is known about the Seven-Tails but since it is a tailed beast, it is able to use the Tailed Beast Ball. It also has the ability to fly.

Shinobi World War Arc
After Son Gokū is resealed into the Demonic Statue of the Outer Path, Tobi, who is intent on going all-out from this point on, forces Fū to fully transform into the Seven-Tails.

Preparing to attack the shinobi, the Seven-Tails along with the other four beasts create Tailed Beast Balls. These attacks however, are deflected by Naruto and they are rebuffed by a now fully-transformed Naruto. After being grabbed mid-flight by the Nine-Tails, and send plummeting to the ground and the other failed attacks by the other beasts, they prepare a collaborative Tailed Beast Ball which is met by one from Naruto and the Nine-Tails.

As Naruto enters a deeper plain of the tailed beasts' consciousness, Chōmei introduces itself to the young man. Later as the beast is freed from the chakra receiver it affirms Kurama's belief that Naruto was the person the Sage of the Six Paths had spoken about so long ago before being resealed into the Demonic Statue of the Outer Path.

Influence
The is among the largest of beetles found in the world. They are also among the strongest animals on the planet in relation to their own size. Its penchant for fighting other males of the species has made them a popular gambling subject in Asia. Beetles are characterised by a hard exoskeleton and fore-wings, which creates a flexible armoured defence. The fore-wings are not used for flight, but tend to cover the hind part of the body and protect the second pair of wings that are used for that purpose. It is also frequently depicted in popular media as a common cartoon character for various uses.

Trivia

 * 'Chōmei' literally mean 'Principal Brightness' or 'Principal Vidya'.