Semaiumi

"Boy, heed me for once and open your ears and remove the wax from between them while your at it. I can see the wax from here, it's that bad! Now on a seperate note, if you ever hear tell of the famous whirlpools out near Heisekai in the spiritual seas suddenly stopping for the first time since they first appeared, you had better be quick in hightailing it over there or my reprimand will be the least of your worries."

- Garian to Kentaro, regarding Semaiumi.

Semaiumi (狭い海, Confined Ocean) is one of the seven Kyūtai forged by an unnamed Kidō master centuries ago. Its current location is unknown to all save Garian Shinjo and Ino Hiroshi, though Garian has hinted to its location in conversations with Kentaro Hiroshi. Garian said it was around the spiritual realm of Heisekai, near a large number of whirlpools within the Spiritual Sea. Before it was sealed, Semaiumi was bonded to Ino.

Powers
Healing Powers: Ino Hiroshi, having seen the orb in use briefly during her training with Garian when he was still in possession of the orb has revealed its healing powers to be tremendous; surpassing any of the other Kyūtai forged before or after it as well as most forms of healing used today. Its power can revive the dead, heal any wound inflicted and cure disease like it was nothing before its power, using the cleansing power of the waters bound within to accomplish any feat of healing.

Immortality: The owner becomes immune to the ravages of time upon their body, making them un-aging from when they acquired the orb. This ability is shared among all the Kyūtai.

Shape Manipulation: The seven Kyūtai all share the ability to freely change their shape, whether it be a ring, belt or sheath covering.

Behind the Scenes
This is influenced greatly by the seven Ka'kari in the Night Angel Trilogy of novels. The above quote, as well as the orbs location, is also influenced by the same novel.