Crab Spirit

Crab Spirit (タラバガニの精霊) is the spirit of a red king crab and the Guardian Ghost of Kouji Yamada.

About
Apparently, he got along well with Damayaji because his hairstyle looked like a hermit crab. After Damayaji's death, both went to the afterlife together rather quickly.

Anime/Manga Difference
In the 2001 anime series, Yamada has the Centipede Spirit instead of the Crab Spirit.

Trivia
The Crab spirit does not truly appear in the manga and both anime series.