Iwami is a supporting character in Noragami Aragoto, known for his role as the former lead shinki, or divine instrument, of the god of fortune, Ebisu. He is an elderly man, distinguished by his long gray hair which he typically wears in a ponytail, along with long bangs that frame his face. His attire has varied over time, originally appearing in a professional jacket with a white collared shirt and a blue tie, but later he is seen in a more traditional long black kimono over a white one.

In terms of personality, Iwami is defined above all by his profound loyalty and his quiet, calm demeanor. He is a good-natured individual who genuinely cares for his master, Ebisu, yet he rarely shows his emotions openly. This loyalty, however, is a double-edged sword. It compelled him to follow the will of his master's previous incarnations, even when that will involved dangerous pursuits that put Ebisu's own life at risk. His primary motivation is deeply intertwined with his duty. For generations, he was tasked with the solemn responsibility of re-educating each new reincarnation of Ebisu. This meant he was the one to pass down the will of the previous Ebisu to the next, which initially involved encouraging the new god to continue his obsessive and forbidden attempts to control ayakashi, or phantoms. His entire purpose was to serve as a living guide, ensuring that each new Ebisu would carry on the work of the last, no matter the cost.

Iwami's role in the story is central to the arc involving Ebisu. He has been with Ebisu longer than any other shinki, making him the one who knows more about his master than anyone else. This longevity grants him a unique and somber perspective, as he has witnessed the cycle of death and reincarnation of his master many times. As the story progresses, he is forced into exile. Because he endorsed the previous Ebisu's crimes against heavenly law by helping him in his research to control ayakashi, the Heavens pursue him. To protect him from being hunted and killed, the newly reincarnated Ebisu is compelled to release him. Iwami is then forced to hide in the residence of the war god Bishamonten, unable to remain by his master's side. His key relationships are primarily with Ebisu, whom he serves with unwavering dedication, and later with Bishamonten, who offers him shelter and eventually begins to question him about his vast knowledge of Heaven's secret history, particularly an ancient war between the Heavens and previous local gods.

The character undergoes a significant but quiet development. For countless reincarnations, he faithfully transmitted a will that encouraged Ebisu to sacrifice himself in his quest. However, after the intervention of the protagonist Yato, the will he is to pass on changes. His new directive for Ebisu is to value his own life and not sacrifice it for the sake of others. This marks a profound shift in his purpose, freeing his master from the cycle of self-destructive ambition. As for notable abilities, as a shinki, his primary function is to serve his god. However, his most remarkable ability is not combat-oriented but rather his immense knowledge and experience. Having lived for centuries and served countless incarnations of Ebisu, he is implied to be one of the longest-serving shinki in the series, possessing knowledge of Heaven's ancient and closely guarded secrets that other characters are eager to learn.