Kagerōmaru

Kageromaru is the demon who lives inside his younger brother Juromaru. He is also one of Naraku's attachments. It is seen later in the episode that Kageromaru is the one, and only one who seems to have control of Juromaru, due to Juromaru immediately slaying his "master" (Naraku's demon puppet) once his shackles were removed. Kageromaru is slowed due to Sango pouring a miasma into the dirt that seems to considerably slow Kageromaru down. Kageromaru is then kicked by Koga, and finished off with InuYasha's Wind Scar.

Abilities
Digging: Kageromaru has the ability to dig deep in the soil, and pop up out of the ground at any given time.

Speed: Kageromaru, as well as his brother Juromaru, have superior speed. However, Kageromaru's speed is arguably at least twice as fast as Koga's.

Name meaning
Kagero's name could mean "one who rows through the shadows"