Naga is a former human who entered a world without humans in order to research how Pokemon who never saw humans acted. What she didn't expect was to crash into the wandering spirit of a selfish, arrogant Serperior known only as Serpent and merge with him. He's constantly whispering advice in her "ears". Admittedly the advice is sound, but she'd rather he just shut up.
She's struggling to deal with her new dual nature. Neither physically human nor mentally Pokemon, she has to unite conflicting impulses, the tool use and logic of humanity versus the instinctive talents of Pokemon.