Otegine

One of the world's three great spears, a spear made by the swordsmith Gojou Gisuke/Yoshisuke from the Suruga Province, Shimada. Because of the Sankin-kotai, he is fitted with a huge scabbard from which his name was based. Since he was crafted to be specialized in piercing, he gets along well with the wakizashi who supports him.

(Source: Touken Ranbu Wiki)