Seireitou Kawahiru (川昼の精霊頭, Kawahiru Seireitō), feared throughout the land by his full title as "Silver-haired Seireitou, Warlord of the Northern Lands", is a powerful yōkai and the adoptive son of the Great Dog Demon. Similar to his step-siblings, Inuyasha and Sesshōmaru, he wields the third sword of their father's fang, the Sō'unga. However, unbeknownst to the two dog demons, Seireitou had forged his own blade with the help of Totosai using his own fang; thus forging the mighty Tennōseiga.