Shishinki

Unknown to either Inuyasha or Sesshomaru, Shishinki was once one of their father's opponents. His powerful Meido Zangetsuha was taken by their father and turned against the demon, ripping half of his head off. Shishinki hides the missing portion of his head behind a mask, masking the severe damage inflicted by the great dog demon. Wielding his staff, Shishinki is able to open numerous portals which suck their victims straight to hell itself. Shishinki is a very cocky opponent who first encounters Sesshomaru when his eyeless assistant lures the demon into a trap. Shishinki takes great pleasure in teasing Sesshomaru about his inability to master the Meido Zangetsuha technique that Sesshomaru's father stole from him, and he recounts the story of how Tenseiga was created from Tetsusaiga, much to the disgust of Sesshomaru. Shishinki's cockiness, leads him to underestimate Sesshomaru and Inuyasha, who work together to defeat the masked demon. Ultimately he is cast into hell by his own technique, used against him by Sesshomaru.

The Meaning Behind the Name
Shishinki's name is written with the kanji for "death", "god" and "oni" which is a type of Japanese demon. "Death God" is a fitting name for someone who can send his opponents directly to hell.