He was the grandfather of Taki Tooru. He did research on youkai throughout his life but had no ability to see them. He died when Taki was still small.
Only appeared in the Episode 31, The Thing That Lurks in The Storeroom.
History
From his younger days, he always sat by the window, reading into books about the supernaturals and youkais, left by their Onmyouji predecessor.
Throughout his life, he was unaware that there were youkais surrounding him all the time. Even though he had no ability to see the spirits, he had power to use the sealing charm.
These could be seen when he successfully sealed Kakura without knowing so.
However, also due to his limited ability, he only managed to create half-seal all around the house.