Kyodai was a spirit entity from Kamigawa, an important part of O-Kagachi himself, who was stolen from the Kakuriyo and imprisoned by daimyo Takeshi Konda in a stone disk known as That Which Was Taken, or simply The Taken One.[1] This act was the primary cause of the Kami War.
Kyodai was bound to Michiko Konda, the daimyo's daughter. With the help of Toshiro Umezawa she was freed from the disk and manifested physically. She looked like Michiko's serpentine twin. Her name means "sibling". Kyodai brought Michiko in the Kakuriyo, showing her how was her life before been kidnapped by Konda and how awful it became during her last twenty years, spent imprisoned in stone. After that she gave to Michiko the powers to fight alongside her.
Michiko and Kyodai, known together as the Sisters of Flesh and Spirit, defeated Konda and O-Kagachi, and claimed themselves the guardians of the barrier between the Utsushiyo and the Kakuriyo.
Many centuries after the Kami War, when Leshrac Nightwalker planeswalked near Kamigawa, the Sisters stood in his way, ordered him to go away from their plane.