OVA
Description
Nachi Igarashi is the elder of the two Igarashi brothers and works as a computer programmer. He shares his home with his younger brother Toshi and two interdimensional beings, Compiler and Assembler, who originally came to Earth with the intention of conquering it but chose to stay and live in the human world. Nachi is the partner of Compiler, and their bond is central to the story.

In personality, Nachi is the antithesis of a structured, predictable life. He despises routine and the workaday world, instead craving constant excitement and stimulation. His passions include wine, women, street racing, gambling, and drinking—interests he enthusiastically shares with Compiler. He is described as freewheeling, charismatic, and always in pursuit of the high life. This hedonistic, thrill-seeking nature drives much of the pair’s adventures and keeps Compiler engaged and challenged.

Nachi’s motivations revolve around avoiding boredom and seeking pleasure and novelty. He has little patience for monotony and is always looking for the next thrill, whether it is a high-stakes race or a night of drinking. This pursuit of excitement gives Compiler a new purpose and constant challenges, preventing her from falling into the kind of dull existence she escaped from her own dimension.

Within the story, Nachi serves as the human counterpart and partner to Compiler. His exuberant, risk-taking attitude contrasts sharply with his brother Toshi’s more cautious and steady nature. While Toshi craves normalcy and is shy, Nachi embraces chaos and social adventure. Together, Nachi and Compiler form a mischievous, fun-loving duo, often dragging those around them into outrageous situations. His role is to provide a bridge between the extraordinary powers of the Routines and the ordinary world of humans, grounding the fantastic elements in relatable, everyday mischief.

Nachi’s relationship with Compiler is marked by mutual affection and camaraderie. They share a deep understanding and enjoyment of the same reckless pastimes. He also interacts with his brother Toshi as a foil—his wildness highlighting Toshi’s restraint. The relationship with their father, Papa Igarashi, is strained and comedic, as the father often intrudes with troublesome inventions.

There is little explicit character development shown; Nachi remains consistently a free-spirited adventurer throughout the series. He does not undergo a dramatic transformation but instead acts as a steady catalyst for the story’s comedic and action-driven turns.

In terms of abilities, Nachi does not possess any supernatural powers. His skills lie in his charm, his knowledge of computer programming, and his talent for street racing and gambling. These abilities are mundane but effective in navigating the chaotic world he shares with Compiler and Assembler.
Cast