Worst (TAKAHASHI Hiroshi) - Vol. 8 Ch. 31 - Corner the Scorpions

[MangaDex]

 

[rxncxd]

Apparently anpan is paint thinner, so the guy was actually addicted to huffing inhalants.

 

[DudeInThePurpleHat]

Yamamoto got addicted to a drug and him getting clean caused him to leave the gang