
Zoro refers to himself as "King of Hell" while finishing "King", Alber who is supposed to represent some kinda angelic figure.
Imu has devil tail arrows and Sabo referred to Mary Geoise as "hell". Also Wapol's wife Kinderella said "Where the Devil have you been?". Oda is emphasizing through this chapter that Mary Geoise is the hell on this planet and Imu the devil ruling over it.
We now have two "Kings"(in IMu's case maybe also queen) of "Hell".
Imu is representing the Lucifer, the fallen angel who wants to replace god but became known as the "devil" or "satan".
Zoro will kill Imu because Luffy is not a killer per se and Zoro probably has better means with his swords and agility to deliver an executing blow.
Aight, that's it for now!
