Apparently, he got along well with Damayaji because his hairstyle looked like a hermit crab. After Damayaji's death, both sent to the afterlife together rather quickly.
See More: Centipede Spirit
In the Anime Series, Yamada has a large teal green centipede-like spirit instead of the Crab Spirit 
- Shaman King Manga - Kang Zeng Bang Volume 9 Extras; Shaman File 116
- Shaman King Anime - Episode 35