Nintōjō

The, also known as the Staff of Two Heads in the English version of the anime, was the weapon which Jaken wielded. It could produce long streams of flame, and generated large floods of water.

After Sesshōmaru saved Jaken and his imp tribe from being slaughtered, the demon imp decided to follow him from then onward. Sesshōmaru retrieved the Staff from a waterfall and gave it to Jaken. If he could wield it, he would be allowed to join Sesshōmaru on his travels.

Physical description
It looks like the name it was given. On half of the top of the staff, sat the head of an old man, and on the other, sat the head of a once-beautiful woman with silky black hair. The staff is taller than Jaken himself, though he is capable of carrying and using it with relative ease.

Powers & Abilities
The Nintōjō has very few demonic abilities displayed. The old man head can spew an impressive amount of fire upon Jaken's command. When close to the grave of Tōga to hit the Black Pearl, the old man's head laughs, but when at the wrong place, the woman's head shrieks.

At the location of the Tōga's stone tomb, Jaken retains the Nintōjō, which can still spew fire from the old man's head. Jaken did the same thing to fight by Inuyasha's side against the Panther Devas of the Panther tribe: Shunran as he spew the fire to dispel her illusion in front of the panther fortress.

After Sesshōmaru attacked Joka and sliced her arms and stole Gold and Silver Rainbow Pearls, Jaken put up a pale blue demonic energy barrier so Zero will never able to them. Four years later, after Zero ordered Homura to burn the forest, Jaken had found Setsuna, but can't find Towa as he told her not move and to put up a demonic barrier before he reported to Rin in the Sacred Tree of Ages.

As the fourteen years went by, it was revealed, from its own lake, that it can clearly project images and sounds of whatever Jaken sees in the physical world, as it had projected images of the infant Moroha while she was growing up from time to time to give then some solace during Inuyasha and Kagome Higurashi's incarceration.

Trivia

 * The Nintōgō dates back to Japan's earliest history. It was meant to symbolize the impermanence of life. It was associated with Enma, the most important of the 10 Kings of Hell, who is sometimes shown holding this object. Enma is associated with long life and protection from illness and misfortune. Artwork of the 10 Kings includes a staff surmounted with two human heads that comprise one male and one female. This object is known as the Dandatō (檀拏幢).
 * The two heads assist the kings during the trials of the deceased. The male head, known as, is shown with its mouth open, for he is reporting the misdeeds of the deceased. The female head, known as , is shown with its mouth closed. A person must appear before Enma and the other judges of hell when they die. They determine whether the person is good or bad. The person is then reborn into the most appropriate of the six realms.
 * It is linked to the Lake of the Staff of Two Heads near Tōga's tomb at the Border of the Afterlife.