The first quality of Kieko Furakura we encounter is an intense utilitarianism. When, as a child, she finds a dead bird at the park, her first thought is that her father loves to eat dead bird, and gets confused when her mother and the other children give it a burial. When she’s in grade school, and everyone is yelling at two boys to stop fighting, she hits one over the head with a garden tool. Everyone’s horror is a mystery to her because as far as she’s concerned, she simply chose the most efficient path. This sets the tone for the book, which is concerned with utility in every moment.

Exactly why Furakura is weird is left up to speculation, which I’d rather not do too much of because it doesn’t matter. She is the way she is, and it primed her to find the convenience store a welcoming place because it’s the first time she was given instructions on how to be normal. Like every other employee, she is told a way to smile, a way to talk, and a way to think, but she embraces these more fully than any other employee. As a result, we catch up to her when she’s been in this job for eighteen years, much longer than anyone would expect. At that point, she’s become a well-honed tool, anticipating customer needs based on weather and reading their minute sounds and movements to react to their needs before they’re even expressed.

Throughout the book, there’s a running commentary on sameness. The convenience store is always exactly the same, according to customers, despite new workers frequently appearing and familiar ones leaving. So too, is society. Through the character of Shiraha, a pathetic man approaching 40 who gets a job, the book expresses a view that society hasn’t changed since the stone age: men are supposed to fill one role, women another, and foreign objects who cannot fulfill those roles are marginalized or expelled. This is where the ship of Theseus comes in.

The convenience store is posed as a ship. The parts change, but the overall object remains exactly the same. This is because the parts are not what constitute the ship, but the object-roles they fulfill. Each employee is trained to speak and act in a precise and identical way, so that no matter which configuration of them is in place, the employee role is fulfilled in exactly the same manner. Should one quit and another start up, the object-role does not change, and as long as the employee fulfills it, the ship remains exactly the same.

Shiraha shows us quickly what happens when an employee doesn’t fulfill the designated object-role. The store expels him, unable to tolerate a part not fulfilling its role. Which is not to say that the convenience store has changed, as he works there. For the object-role is still the same, and all that needs to happen is the expulsion of the foreign object. This happens quickly. Shiraha is soon fired, and the convenience store returns to normal.

This particular ship overlaps with a larger one. People are expected to be a part of the convenience store temporarily, and then move on to fulfill an object-role in society. For Furakura, this means that she’s expected either to marry or move on to a “real” job. That she hasn’t makes her an aberration, a foreign object, and in her limited social exposure early in the book, she makes vague excuses about her health to explain why she hasn’t moved on. Society has valid object-roles for the sick, but once doubt gets cast on her excuses, she finds herself under pressure to conform to her appropriate role, not least from Shiraha.

Furakura’s perfection as a part of the lesser ship, her happiness at being that part, and the pressure to leave that behind create a puzzle. Her continuation at the convenience store both is and isn’t a victory. As she listens to the convenience store and absorbs all of the factors she sees and optimizes it for best customer experience, she gets a taste of the sublime. But this taste is only possible because her experience as a child hollowed her out, and taught her to have no judgement and become nothing, for fear of upsetting others. A foreign object turned into an empty vessel rather than expelled, which could be filled by the object-role of convenience store worker fully and completely. What she would have been if she’d been left up to her own judgement is lost, and the ship cruises atop the water, unchanged since antiquity.