Drug-dealing scumbag crimelord Kanryu Takeda: corrupt drug dealer and tycoon who murders Megumi's ex-boss, then forces her to prepare a highly lethal brand of opium via killing her boss and enslaving her, then breaks her further via a Sadistic Choice, and ultimately kills Aoshi's Oniwabanshu subordinates with a gatling gun, pushing him towards the Despair Event Horizon.
Gein, Enishi's Dragon. He's a Psycho for Hire, Blood Knight, and an all around sicko who joins Enishi's campaign and offers him advice on Mind Rape-ing Kenshin, not for revenge, but for kicks and a chance to test his abilities. He makes puppets out of corpses, kills or murders pretty much everyone who crosses his path, works as an arms dealer, sees war as a chance for fun and intellectual masturbation, and was the mastermind behind the plan to fake Kaoru's murder, just to screw with Kenshin's head. On top of that, he was named afterEd Gein.